（六十九）c#Winform自定义控件-垂直滚动条
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2022-08-05 23:14:34
前提 入行已经7,8年了，一直想做一套漂亮点的自定义控件，于是就有了本系列文章。 GitHub：https://github.com/kwwwvagaa/NetWinformControl 码云：https://gitee.com/kwwwvagaa/net_winform_custom_contr ......
前提
入行已经7,8年了，一直想做一套漂亮点的自定义控件，于是就有了本系列文章。
github：https://github.com/kwwwvagaa/netwinformcontrol
码云：
如果觉得写的还行，请点个 star 支持一下吧
欢迎前来交流探讨： 企鹅群568015492
麻烦博客下方点个【推荐】，谢谢
nuget
install-package hzh_controls
目录
用处及效果
目前支持scrollablecontrol，treeview，textbox的滚动条，只需要在相应的界面上添加组件scrollbarcomponent即可
准备工作
用到了（一）c#winform自定义控件-基类控件 ，如果你还不了解，可以先去看一下
自定义滚动条有2种方式，1：拦截windows消息，重绘，2：做一个新的，盖上去挡着，这里我们采用的是第二种。
开始
添加一个类ucvscrollbar，继承uccontrolbase
一些属性
1 /// <summary>
2 /// the mo large change
3 /// </summary>
4 protected int molargechange = 10;
5 /// <summary>
6 /// the mo small change
7 /// </summary>
8 protected int mosmallchange = 1;
9 /// <summary>
10 /// the mo minimum
11 /// </summary>
12 protected int mominimum = 0;
13 /// <summary>
14 /// the mo maximum
15 /// </summary>
16 protected int momaximum = 100;
17 /// <summary>
18 /// the mo value
19 /// </summary>
20 protected int movalue = 0;
21 /// <summary>
22 /// the n click point
23 /// </summary>
24 private int nclickpoint;
25 /// <summary>
26 /// the mo thumb top
27 /// </summary>
28 protected int mothumbtop = 0;
29 /// <summary>
30 /// the mo automatic size
31 /// </summary>
32 protected bool moautosize = false;
33 /// <summary>
34 /// the mo thumb down
35 /// </summary>
36 private bool mothumbdown = false;
37 /// <summary>
38 /// the mo thumb dragging
39 /// </summary>
40 private bool mothumbdragging = false;
41 /// <summary>
42 /// occurs when [scroll].
43 /// </summary>
44 public new event eventhandler scroll = null;
45 /// <summary>
46 /// occurs when [value changed].
47 /// </summary>
48 public event eventhandler valuechanged = null;
49
50 /// <summary>
51 /// the btn height
52 /// </summary>
53 private int btnheight = 18;
54 /// <summary>
55 /// the m int thumb minimum height
56 /// </summary>
57 private int m_intthumbminheight = 15;
58
59 /// <summary>
60 /// gets or sets the height of the btn.
61 /// </summary>
62 /// <value>the height of the btn.</value>
63 public int btnheight
64 {
65 get { return btnheight; }
66 set { btnheight = value; }
67 }
68 /// <summary>
69 /// gets or sets the large change.
70 /// </summary>
71 /// <value>the large change.</value>
72 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("largechange")]
73 public int largechange
74 {
75 get { return molargechange; }
76 set
77 {
78 molargechange = value;
79 invalidate();
80 }
81 }
82
83 /// <summary>
84 /// gets or sets the small change.
85 /// </summary>
86 /// <value>the small change.</value>
87 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("smallchange")]
88 public int smallchange
89 {
90 get { return mosmallchange; }
91 set
92 {
93 mosmallchange = value;
94 invalidate();
95 }
96 }
97
98 /// <summary>
99 /// gets or sets the minimum.
100 /// </summary>
101 /// <value>the minimum.</value>
102 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("minimum")]
103 public int minimum
104 {
105 get { return mominimum; }
106 set
107 {
108 mominimum = value;
109 invalidate();
110 }
111 }
112
113 /// <summary>
114 /// gets or sets the maximum.
115 /// </summary>
116 /// <value>the maximum.</value>
117 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("maximum")]
118 public int maximum
119 {
120 get { return momaximum; }
121 set
122 {
123 momaximum = value;
124 invalidate();
125 }
126 }
127
128 /// <summary>
129 /// gets or sets the value.
130 /// </summary>
131 /// <value>the value.</value>
132 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("value")]
133 public int value
134 {
135 get { return movalue; }
136 set
137 {
138 movalue = value;
139
140 int ntrackheight = (this.height - btnheight * 2);
141 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
142 int nthumbheight = (int)fthumbheight;
143
144 if (nthumbheight > ntrackheight)
145 {
146 nthumbheight = ntrackheight;
147 fthumbheight = ntrackheight;
148 }
149 if (nthumbheight < m_intthumbminheight)
150 {
151 nthumbheight = m_intthumbminheight;
152 fthumbheight = m_intthumbminheight;
153 }
154
155 //figure out value
156 int npixelrange = ntrackheight - nthumbheight;
157 int nrealrange = (maximum - minimum) - largechange;
158 float fperc = 0.0f;
159 if (nrealrange != 0)
160 {
161 fperc = (float)movalue / (float)nrealrange;
162
163 }
164
165 float ftop = fperc * npixelrange;
166 mothumbtop = (int)ftop;
167
168
169 invalidate();
170 }
171 }
172
173 /// <summary>
174 /// gets or sets a value indicating whether [automatic size].
175 /// </summary>
176 /// <value><c>true</c> if [automatic size]; otherwise, <c>false</c>.</value>
177 public override bool autosize
178 {
179 get
180 {
181 return base.autosize;
182 }
183 set
184 {
185 base.autosize = value;
186 if (base.autosize)
187 {
188 this.width = 15;
189 }
190 }
191 }
192
193 /// <summary>
194 /// the thumb color
195 /// </summary>
196 private color thumbcolor = color.fromargb(255, 77, 58);
197
198 /// <summary>
199 /// gets or sets the color of the thumb.
200 /// </summary>
201 /// <value>the color of the thumb.</value>
202 public color thumbcolor
203 {
204 get { return thumbcolor; }
205 set { thumbcolor = value; }
206 }
重绘
1 protected override void onpaint(painteventargs e)
2 {
3 base.onpaint(e);
4 e.graphics.setgdihigh();
5
6 //draw thumb
7 int ntrackheight = (this.height - btnheight * 2);
8 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
9 int nthumbheight = (int)fthumbheight;
10
11 if (nthumbheight > ntrackheight)
12 {
13 nthumbheight = ntrackheight;
14 fthumbheight = ntrackheight;
15 }
16 if (nthumbheight < m_intthumbminheight)
17 {
18 nthumbheight = m_intthumbminheight;
19 fthumbheight = m_intthumbminheight;
20 }
21 int ntop = mothumbtop;
22 ntop += btnheight;
23 e.graphics.fillpath(new solidbrush(thumbcolor), new rectangle(1, ntop, this.width - 3, nthumbheight).createroundedrectanglepath(this.conerradius));
24
25 controlhelper.painttriangle(e.graphics, new solidbrush(thumbcolor), new point(this.width / 2, btnheight - math.min(5, this.width / 2)), math.min(5, this.width / 2), graphdirection.upward);
26 controlhelper.painttriangle(e.graphics, new solidbrush(thumbcolor), new point(this.width / 2, this.height - (btnheight - math.min(5, this.width / 2))), math.min(5, this.width / 2), graphdirection.downward);
27
28 }
处理下鼠标事件
1 /// <summary>
2 /// handles the mousedown event of the customscrollbar control.
3 /// </summary>
4 /// <param name="sender">the source of the event.</param>
5 /// <param name="e">the <see cref="mouseeventargs"/> instance containing the event data.</param>
6 private void customscrollbar_mousedown(object sender, mouseeventargs e)
7 {
8 point ptpoint = this.pointtoclient(cursor.position);
9 int ntrackheight = (this.height - btnheight * 2);
10 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
11 int nthumbheight = (int)fthumbheight;
12
13 if (nthumbheight > ntrackheight)
14 {
15 nthumbheight = ntrackheight;
16 fthumbheight = ntrackheight;
17 }
18 if (nthumbheight < m_intthumbminheight)
19 {
20 nthumbheight = m_intthumbminheight;
21 fthumbheight = m_intthumbminheight;
22 }
23
24 int ntop = mothumbtop;
25 ntop += btnheight;
26
27
28 rectangle thumbrect = new rectangle(new point(1, ntop), new size(this.width - 2, nthumbheight));
29 if (thumbrect.contains(ptpoint))
30 {
31
32 //hit the thumb
33 nclickpoint = (ptpoint.y - ntop);
34 //messagebox.show(convert.tostring((ptpoint.y - ntop)));
35 this.mothumbdown = true;
36 }
37
38 rectangle uparrowrect = new rectangle(new point(1, 0), new size(this.width, btnheight));
39 if (uparrowrect.contains(ptpoint))
40 {
41
42 int nrealrange = (maximum - minimum) - largechange;
43 int npixelrange = (ntrackheight - nthumbheight);
44 if (nrealrange > 0)
45 {
46 if (npixelrange > 0)
47 {
48 if ((mothumbtop - smallchange) < 0)
49 mothumbtop = 0;
50 else
51 mothumbtop -= smallchange;
52
53 //figure out value
54 float fperc = (float)mothumbtop / (float)npixelrange;
55 float fvalue = fperc * (maximum - largechange);
56
57 movalue = (int)fvalue;
58
59 if (valuechanged != null)
60 valuechanged(this, new eventargs());
61
62 if (scroll != null)
63 scroll(this, new eventargs());
64
65 invalidate();
66 }
67 }
68 }
69
70 rectangle downarrowrect = new rectangle(new point(1, btnheight + ntrackheight), new size(this.width, btnheight));
71 if (downarrowrect.contains(ptpoint))
72 {
73 int nrealrange = (maximum - minimum) - largechange;
74 int npixelrange = (ntrackheight - nthumbheight);
75 if (nrealrange > 0)
76 {
77 if (npixelrange > 0)
78 {
79 if ((mothumbtop + smallchange) > npixelrange)
80 mothumbtop = npixelrange;
81 else
82 mothumbtop += smallchange;
83
84 //figure out value
85 float fperc = (float)mothumbtop / (float)npixelrange;
86 float fvalue = fperc * (maximum - largechange);
87
88 movalue = (int)fvalue;
89
90 if (valuechanged != null)
91 valuechanged(this, new eventargs());
92
93 if (scroll != null)
94 scroll(this, new eventargs());
95
96 invalidate();
97 }
98 }
99 }
100 }
101
102 /// <summary>
103 /// handles the mouseup event of the customscrollbar control.
104 /// </summary>
105 /// <param name="sender">the source of the event.</param>
106 /// <param name="e">the <see cref="mouseeventargs"/> instance containing the event data.</param>
107 private void customscrollbar_mouseup(object sender, mouseeventargs e)
108 {
109 this.mothumbdown = false;
110 this.mothumbdragging = false;
111 }
112
113 /// <summary>
114 /// moves the thumb.
115 /// </summary>
116 /// <param name="y">the y.</param>
117 private void movethumb(int y)
118 {
119 int nrealrange = maximum - minimum;
120 int ntrackheight = (this.height - btnheight * 2);
121 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
122 int nthumbheight = (int)fthumbheight;
123
124 if (nthumbheight > ntrackheight)
125 {
126 nthumbheight = ntrackheight;
127 fthumbheight = ntrackheight;
128 }
129 if (nthumbheight < m_intthumbminheight)
130 {
131 nthumbheight = m_intthumbminheight;
132 fthumbheight = m_intthumbminheight;
133 }
134
135 int nspot = nclickpoint;
136
137 int npixelrange = (ntrackheight - nthumbheight);
138 if (mothumbdown && nrealrange > 0)
139 {
140 if (npixelrange > 0)
141 {
142 int nnewthumbtop = y - (btnheight + nspot);
143
144 if (nnewthumbtop < 0)
145 {
146 mothumbtop = nnewthumbtop = 0;
147 }
148 else if (nnewthumbtop > npixelrange)
149 {
150 mothumbtop = nnewthumbtop = npixelrange;
151 }
152 else
153 {
154 mothumbtop = y - (btnheight + nspot);
155 }
156
157
158 float fperc = (float)mothumbtop / (float)npixelrange;
159 float fvalue = fperc * (maximum - largechange);
160 movalue = (int)fvalue;
161
162 application.doevents();
163
164 invalidate();
165 }
166 }
167 }
168
169 /// <summary>
170 /// handles the mousemove event of the customscrollbar control.
171 /// </summary>
172 /// <param name="sender">the source of the event.</param>
173 /// <param name="e">the <see cref="mouseeventargs"/> instance containing the event data.</param>
174 private void customscrollbar_mousemove(object sender, mouseeventargs e)
175 {
176 if (!mothumbdown)
177 return;
178
179 if (mothumbdown == true)
180 {
181 this.mothumbdragging = true;
182 }
183
184 if (this.mothumbdragging)
185 {
186 movethumb(e.y);
187 }
188
189 if (valuechanged != null)
190 valuechanged(this, new eventargs());
191
192 if (scroll != null)
193 scroll(this, new eventargs());
194 }
完整代码
1 // ***********************************************************************
2 // assembly : hzh_controls
3 // created : 2019-09-19
4 //
5 // ***********************************************************************
6 // <copyright file="ucvscrollbar.cs">
7 // copyright by huang zhenghui(黄正辉) all, qq group:568015492 qq:623128629 email:623128629@qq.com
8 // </copyright>
9 //
10 // blog: https://www.cnblogs.com/bfyx
11 // github：https://github.com/kwwwvagaa/netwinformcontrol
12 // gitee：https://gitee.com/kwwwvagaa/net_winform_custom_control.git
13 //
14 // if you use this code, please keep this note.
15 // ***********************************************************************
16 using system;
17 using system.collections.generic;
18 using system.componentmodel;
19 using system.drawing;
20 using system.data;
21 using system.text;
22 using system.windows.forms;
23 using system.windows.forms.design;
24 using system.diagnostics;
25
26
27 namespace hzh_controls.controls
28 {
29
30 /// <summary>
31 /// class ucvscrollbar.
32 /// implements the <see cref="hzh_controls.controls.uccontrolbase" />
33 /// </summary>
34 /// <seealso cref="hzh_controls.controls.uccontrolbase" />
35 [designer(typeof(scrollbarcontroldesigner))]
36 [defaultevent("scroll")]
37 public class ucvscrollbar : uccontrolbase
38 {
39 /// <summary>
40 /// the mo large change
41 /// </summary>
42 protected int molargechange = 10;
43 /// <summary>
44 /// the mo small change
45 /// </summary>
46 protected int mosmallchange = 1;
47 /// <summary>
48 /// the mo minimum
49 /// </summary>
50 protected int mominimum = 0;
51 /// <summary>
52 /// the mo maximum
53 /// </summary>
54 protected int momaximum = 100;
55 /// <summary>
56 /// the mo value
57 /// </summary>
58 protected int movalue = 0;
59 /// <summary>
60 /// the n click point
61 /// </summary>
62 private int nclickpoint;
63 /// <summary>
64 /// the mo thumb top
65 /// </summary>
66 protected int mothumbtop = 0;
67 /// <summary>
68 /// the mo automatic size
69 /// </summary>
70 protected bool moautosize = false;
71 /// <summary>
72 /// the mo thumb down
73 /// </summary>
74 private bool mothumbdown = false;
75 /// <summary>
76 /// the mo thumb dragging
77 /// </summary>
78 private bool mothumbdragging = false;
79 /// <summary>
80 /// occurs when [scroll].
81 /// </summary>
82 public new event eventhandler scroll = null;
83 /// <summary>
84 /// occurs when [value changed].
85 /// </summary>
86 public event eventhandler valuechanged = null;
87
88 /// <summary>
89 /// the btn height
90 /// </summary>
91 private int btnheight = 18;
92 /// <summary>
93 /// the m int thumb minimum height
94 /// </summary>
95 private int m_intthumbminheight = 15;
96
97 /// <summary>
98 /// gets or sets the height of the btn.
99 /// </summary>
100 /// <value>the height of the btn.</value>
101 public int btnheight
102 {
103 get { return btnheight; }
104 set { btnheight = value; }
105 }
106 /// <summary>
107 /// gets or sets the large change.
108 /// </summary>
109 /// <value>the large change.</value>
110 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("largechange")]
111 public int largechange
112 {
113 get { return molargechange; }
114 set
115 {
116 molargechange = value;
117 invalidate();
118 }
119 }
120
121 /// <summary>
122 /// gets or sets the small change.
123 /// </summary>
124 /// <value>the small change.</value>
125 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("smallchange")]
126 public int smallchange
127 {
128 get { return mosmallchange; }
129 set
130 {
131 mosmallchange = value;
132 invalidate();
133 }
134 }
135
136 /// <summary>
137 /// gets or sets the minimum.
138 /// </summary>
139 /// <value>the minimum.</value>
140 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("minimum")]
141 public int minimum
142 {
143 get { return mominimum; }
144 set
145 {
146 mominimum = value;
147 invalidate();
148 }
149 }
150
151 /// <summary>
152 /// gets or sets the maximum.
153 /// </summary>
154 /// <value>the maximum.</value>
155 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("maximum")]
156 public int maximum
157 {
158 get { return momaximum; }
159 set
160 {
161 momaximum = value;
162 invalidate();
163 }
164 }
165
166 /// <summary>
167 /// gets or sets the value.
168 /// </summary>
169 /// <value>the value.</value>
170 [editorbrowsable(editorbrowsablestate.always), browsable(true), defaultvalue(false), category("自定义"), description("value")]
171 public int value
172 {
173 get { return movalue; }
174 set
175 {
176 movalue = value;
177
178 int ntrackheight = (this.height - btnheight * 2);
179 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
180 int nthumbheight = (int)fthumbheight;
181
182 if (nthumbheight > ntrackheight)
183 {
184 nthumbheight = ntrackheight;
185 fthumbheight = ntrackheight;
186 }
187 if (nthumbheight < m_intthumbminheight)
188 {
189 nthumbheight = m_intthumbminheight;
190 fthumbheight = m_intthumbminheight;
191 }
192
193 //figure out value
194 int npixelrange = ntrackheight - nthumbheight;
195 int nrealrange = (maximum - minimum) - largechange;
196 float fperc = 0.0f;
197 if (nrealrange != 0)
198 {
199 fperc = (float)movalue / (float)nrealrange;
200
201 }
202
203 float ftop = fperc * npixelrange;
204 mothumbtop = (int)ftop;
205
206
207 invalidate();
208 }
209 }
210
211 /// <summary>
212 /// gets or sets a value indicating whether [automatic size].
213 /// </summary>
214 /// <value><c>true</c> if [automatic size]; otherwise, <c>false</c>.</value>
215 public override bool autosize
216 {
217 get
218 {
219 return base.autosize;
220 }
221 set
222 {
223 base.autosize = value;
224 if (base.autosize)
225 {
226 this.width = 15;
227 }
228 }
229 }
230
231 /// <summary>
232 /// the thumb color
233 /// </summary>
234 private color thumbcolor = color.fromargb(255, 77, 58);
235
236 /// <summary>
237 /// gets or sets the color of the thumb.
238 /// </summary>
239 /// <value>the color of the thumb.</value>
240 public color thumbcolor
241 {
242 get { return thumbcolor; }
243 set { thumbcolor = value; }
244 }
245
246 /// <summary>
247 /// initializes a new instance of the <see cref="ucvscrollbar"/> class.
248 /// </summary>
249 public ucvscrollbar()
250 {
251 initializecomponent();
252 conerradius = 2;
253 fillcolor = color.fromargb(239, 239, 239);
254 isshowrect = false;
255 isradius = true;
256 this.setstyle(controlstyles.allpaintinginwmpaint, true);
257 this.setstyle(controlstyles.doublebuffer, true);
258 this.setstyle(controlstyles.resizeredraw, true);
259 this.setstyle(controlstyles.selectable, true);
260 this.setstyle(controlstyles.supportstransparentbackcolor, true);
261 this.setstyle(controlstyles.userpaint, true);
262 }
263
264
265
266
267 /// <summary>
268 /// 引发 <see cref="e:system.windows.forms.control.paint" /> 事件。
269 /// </summary>
270 /// <param name="e">包含事件数据的 <see cref="t:system.windows.forms.painteventargs" />。</param>
271 protected override void onpaint(painteventargs e)
272 {
273 base.onpaint(e);
274 e.graphics.setgdihigh();
275
276 //draw thumb
277 int ntrackheight = (this.height - btnheight * 2);
278 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
279 int nthumbheight = (int)fthumbheight;
280
281 if (nthumbheight > ntrackheight)
282 {
283 nthumbheight = ntrackheight;
284 fthumbheight = ntrackheight;
285 }
286 if (nthumbheight < m_intthumbminheight)
287 {
288 nthumbheight = m_intthumbminheight;
289 fthumbheight = m_intthumbminheight;
290 }
291 int ntop = mothumbtop;
292 ntop += btnheight;
293 e.graphics.fillpath(new solidbrush(thumbcolor), new rectangle(1, ntop, this.width - 3, nthumbheight).createroundedrectanglepath(this.conerradius));
294
295 controlhelper.painttriangle(e.graphics, new solidbrush(thumbcolor), new point(this.width / 2, btnheight - math.min(5, this.width / 2)), math.min(5, this.width / 2), graphdirection.upward);
296 controlhelper.painttriangle(e.graphics, new solidbrush(thumbcolor), new point(this.width / 2, this.height - (btnheight - math.min(5, this.width / 2))), math.min(5, this.width / 2), graphdirection.downward);
297
298 }
299
300 /// <summary>
301 /// initializes the component.
302 /// </summary>
303 private void initializecomponent()
304 {
305 this.suspendlayout();
306 //
307 // ucvscrollbar
308 //
309 this.minimumsize = new system.drawing.size(10, 0);
310 this.name = "ucvscrollbar";
311 this.size = new system.drawing.size(18, 150);
312 this.mousedown += new system.windows.forms.mouseeventhandler(this.customscrollbar_mousedown);
313 this.mousemove += new system.windows.forms.mouseeventhandler(this.customscrollbar_mousemove);
314 this.mouseup += new system.windows.forms.mouseeventhandler(this.customscrollbar_mouseup);
315 this.resumelayout(false);
316
317 }
318
319 /// <summary>
320 /// handles the mousedown event of the customscrollbar control.
321 /// </summary>
322 /// <param name="sender">the source of the event.</param>
323 /// <param name="e">the <see cref="mouseeventargs"/> instance containing the event data.</param>
324 private void customscrollbar_mousedown(object sender, mouseeventargs e)
325 {
326 point ptpoint = this.pointtoclient(cursor.position);
327 int ntrackheight = (this.height - btnheight * 2);
328 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
329 int nthumbheight = (int)fthumbheight;
330
331 if (nthumbheight > ntrackheight)
332 {
333 nthumbheight = ntrackheight;
334 fthumbheight = ntrackheight;
335 }
336 if (nthumbheight < m_intthumbminheight)
337 {
338 nthumbheight = m_intthumbminheight;
339 fthumbheight = m_intthumbminheight;
340 }
341
342 int ntop = mothumbtop;
343 ntop += btnheight;
344
345
346 rectangle thumbrect = new rectangle(new point(1, ntop), new size(this.width - 2, nthumbheight));
347 if (thumbrect.contains(ptpoint))
348 {
349
350 //hit the thumb
351 nclickpoint = (ptpoint.y - ntop);
352 //messagebox.show(convert.tostring((ptpoint.y - ntop)));
353 this.mothumbdown = true;
354 }
355
356 rectangle uparrowrect = new rectangle(new point(1, 0), new size(this.width, btnheight));
357 if (uparrowrect.contains(ptpoint))
358 {
359
360 int nrealrange = (maximum - minimum) - largechange;
361 int npixelrange = (ntrackheight - nthumbheight);
362 if (nrealrange > 0)
363 {
364 if (npixelrange > 0)
365 {
366 if ((mothumbtop - smallchange) < 0)
367 mothumbtop = 0;
368 else
369 mothumbtop -= smallchange;
370
371 //figure out value
372 float fperc = (float)mothumbtop / (float)npixelrange;
373 float fvalue = fperc * (maximum - largechange);
374
375 movalue = (int)fvalue;
376
377 if (valuechanged != null)
378 valuechanged(this, new eventargs());
379
380 if (scroll != null)
381 scroll(this, new eventargs());
382
383 invalidate();
384 }
385 }
386 }
387
388 rectangle downarrowrect = new rectangle(new point(1, btnheight + ntrackheight), new size(this.width, btnheight));
389 if (downarrowrect.contains(ptpoint))
390 {
391 int nrealrange = (maximum - minimum) - largechange;
392 int npixelrange = (ntrackheight - nthumbheight);
393 if (nrealrange > 0)
394 {
395 if (npixelrange > 0)
396 {
397 if ((mothumbtop + smallchange) > npixelrange)
398 mothumbtop = npixelrange;
399 else
400 mothumbtop += smallchange;
401
402 //figure out value
403 float fperc = (float)mothumbtop / (float)npixelrange;
404 float fvalue = fperc * (maximum - largechange);
405
406 movalue = (int)fvalue;
407
408 if (valuechanged != null)
409 valuechanged(this, new eventargs());
410
411 if (scroll != null)
412 scroll(this, new eventargs());
413
414 invalidate();
415 }
416 }
417 }
418 }
419
420 /// <summary>
421 /// handles the mouseup event of the customscrollbar control.
422 /// </summary>
423 /// <param name="sender">the source of the event.</param>
424 /// <param name="e">the <see cref="mouseeventargs"/> instance containing the event data.</param>
425 private void customscrollbar_mouseup(object sender, mouseeventargs e)
426 {
427 this.mothumbdown = false;
428 this.mothumbdragging = false;
429 }
430
431 /// <summary>
432 /// moves the thumb.
433 /// </summary>
434 /// <param name="y">the y.</param>
435 private void movethumb(int y)
436 {
437 int nrealrange = maximum - minimum;
438 int ntrackheight = (this.height - btnheight * 2);
439 float fthumbheight = ((float)largechange / (float)maximum) * ntrackheight;
440 int nthumbheight = (int)fthumbheight;
441
442 if (nthumbheight > ntrackheight)
443 {
444 nthumbheight = ntrackheight;
445 fthumbheight = ntrackheight;
446 }
447 if (nthumbheight < m_intthumbminheight)
448 {
449 nthumbheight = m_intthumbminheight;
450 fthumbheight = m_intthumbminheight;
451 }
452
453 int nspot = nclickpoint;
454
455 int npixelrange = (ntrackheight - nthumbheight);
456 if (mothumbdown && nrealrange > 0)
457 {
458 if (npixelrange > 0)
459 {
460 int nnewthumbtop = y - (btnheight + nspot);
461
462 if (nnewthumbtop < 0)
463 {
464 mothumbtop = nnewthumbtop = 0;
465 }
466 else if (nnewthumbtop > npixelrange)
467 {
468 mothumbtop = nnewthumbtop = npixelrange;
469 }
470 else
471 {
472 mothumbtop = y - (btnheight + nspot);
473 }
474
475
476 float fperc = (float)mothumbtop / (float)npixelrange;
477 float fvalue = fperc * (maximum - largechange);
478 movalue = (int)fvalue;
479
480 application.doevents();
481
482 invalidate();
483 }
484 }
485 }
486
487 /// <summary>
488 /// handles the mousemove event of the customscrollbar control.
489 /// </summary>
490 /// <param name="sender">the source of the event.</param>
491 /// <param name="e">the <see cref="mouseeventargs"/> instance containing the event data.</param>
492 private void customscrollbar_mousemove(object sender, mouseeventargs e)
493 {
494 if (!mothumbdown)
495 return;
496
497 if (mothumbdown == true)
498 {
499 this.mothumbdragging = true;
500 }
501
502 if (this.mothumbdragging)
503 {
504 movethumb(e.y);
505 }
506
507 if (valuechanged != null)
508 valuechanged(this, new eventargs());
509
510 if (scroll != null)
511 scroll(this, new eventargs());
512 }
513
514 }
515
516 /// <summary>
517 /// class scrollbarcontroldesigner.
518 /// implements the <see cref="system.windows.forms.design.controldesigner" />
519 /// </summary>
520 /// <seealso cref="system.windows.forms.design.controldesigner" />
521 internal class scrollbarcontroldesigner : system.windows.forms.design.controldesigner
522 {
523 /// <summary>
524 /// 获取指示组件的移动功能的选择规则。
525 /// </summary>
526 /// <value>the selection rules.</value>
527 public override selectionrules selectionrules
528 {
529 get
530 {
531 selectionrules selectionrules = base.selectionrules;
532 propertydescriptor propdescriptor = typedescriptor.getproperties(this.component)["autosize"];
533 if (propdescriptor != null)
534 {
535 bool autosize = (bool)propdescriptor.getvalue(this.component);
536 if (autosize)
537 {
538 selectionrules = selectionrules.visible | selectionrules.moveable | selectionrules.bottomsizeable | selectionrules.topsizeable;
539 }
540 else
541 {
542 selectionrules = selectionrules.visible | selectionrules.allsizeable | selectionrules.moveable;
543 }
544 }
545 return selectionrules;
546 }
547 }
548 }
549 }
为了方便使用，我们添加一个组件
新增类scrollbarcomponent，继承 component, iextenderprovider
实现接口方法
1 public bool canextend(object extendee)
2 {
3 if (extendee is scrollablecontrol)
4 {
5 scrollablecontrol control = (scrollablecontrol)extendee;
6 if (control.autoscroll == true)
7 {
8 return true;
9 }
10 }
11 else if (extendee is treeview)
12 {
13 treeview control = (treeview)extendee;
14 if (control.scrollable)
15 {
16 return true;
17 }
18 }
19 else if (extendee is textbox)
20 {
21 textbox control = (textbox)extendee;
22 if (control.multiline && control.scrollbars != scrollbars.none)
23 {
24 return true;
25 }
26 }
27 return false;
28 }
扩展控件属性
1 [browsable(true), category("自定义属性"), description("是否使用自定义滚动条"), displayname("usercustomscrollbar"), localizable(true)]
2 public bool getusercustomscrollbar(control control)
3 {
4 return m_blnusercustomscrollbar;
5 }
6
7 public void setusercustomscrollbar(control control, bool blnusercustomscrollbar)
8 {
9 m_blnusercustomscrollbar = blnusercustomscrollbar;
10 control.visiblechanged += control_visiblechanged;
11 control.sizechanged += control_sizechanged;
12 control.locationchanged += control_locationchanged;
13 control.disposed += control_disposed;
14
15 if (control is treeview)
16 {
17 treeview tv = (treeview)control;
18 tv.mousewheel += tv_mousewheel;
19 tv.afterselect += tv_afterselect;
20 tv.afterexpand += tv_afterexpand;
21 tv.aftercollapse += tv_aftercollapse;
22 }
23 else if (control is textbox)
24 {
25 textbox txt = (textbox)control;
26 txt.mousewheel += txt_mousewheel;
27 txt.textchanged += txt_textchanged;
28
29 txt.keydown += txt_keydown;
30 }
31 control_sizechanged(control, null);
32 }
33
处理一下控件什么时候添加滚动条，什么时候移除滚动条，以及滚动条位置大小的改变等
1 void control_disposed(object sender, eventargs e)
2 {
3 control control = (control)sender;
4 if (m_lstvcache.containskey(control) && m_lstvcache[control].parent != null)
5 {
6 m_lstvcache[control].parent.controls.remove(m_lstvcache[control]);
7 m_lstvcache.remove(control);
8 }
9 }
10
11 void control_locationchanged(object sender, eventargs e)
12 {
13 resetvscrolllocation(sender);
14 }
15
16 void control_sizechanged(object sender, eventargs e)
17 {
18 if (controlhelper.isdesignmode())
19 {
20 return;
21 }
22 else
23 {
24 var control = sender as control;
25
26 bool blnhasvscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & vscroll) != 0;
27 bool blnhashscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & hscroll) != 0;
28 if (blnhasvscrollbar)
29 {
30 if (!m_lstvcache.containskey(control))
31 {
32 if (control.parent != null)
33 {
34 ucvscrollbar barv = new ucvscrollbar();
35 barv.scroll += barv_scroll;
36 m_lstvcache[control] = barv;
37 if (blnhashscrollbar)
38 {
39 barv.height = control.height - barv.width - 2;
40 }
41 else
42 {
43 barv.height = control.height - 2;
44 }
45 setvmaxnum(control);
46 barv.location = new system.drawing.point(control.right - barv.width - 1, control.top + 1);
47 control.parent.controls.add(barv);
48 int intcontrolindex = control.parent.controls.getchildindex(control);
49 control.parent.controls.setchildindex(barv, intcontrolindex);
50 }
51 }
52 else
53 {
54 setvmaxnum(control);
55 }
56 }
57 else
58 {
59 if (m_lstvcache.containskey(control) && m_lstvcache[control].parent != null)
60 {
61 m_lstvcache[control].parent.controls.remove(m_lstvcache[control]);
62 m_lstvcache.remove(control);
63 }
64 }
65
66 //if (blnhashscrollbar)
67 //{
68 // if (control.parent != null)
69 // {
70
71 // }
72 //}
73 //else
74 //{
75 // if (m_lsthcache.containskey(control))
76 // {
77 // if (m_lsthcache[control].visible)
78 // {
79 // m_lsthcache[control].parent.controls.remove(m_lsthcache[control]);
80 // }
81 // }
82 //}
83 }
84 resetvscrolllocation(sender);
85 }
86
87 private void setvmaxnum(control control)
88 {
89 if (!m_lstvcache.containskey(control))
90 return;
91 ucvscrollbar barv = m_lstvcache[control];
92 if (control is scrollablecontrol)
93 {
94 barv.maximum = (control as scrollablecontrol).verticalscroll.maximum;
95 barv.value = (control as scrollablecontrol).verticalscroll.value;
96 }
97 else if (control is treeview)
98 {
99 barv.maximum = gettreenodemaxy(control as treeview);
100 barv.value = (control as treeview).autoscrolloffset.y;
101 }
102 else if (control is textbox)
103 {
104 textbox txt = (textbox)control;
105 int inttxtmaxheight = 0;
106 int inttextheight = 0;
107 using (var g = txt.creategraphics())
108 {
109 inttxtmaxheight = (int)g.measurestring(txt.text, txt.font).height;
110 inttextheight = (int)g.measurestring(txt.text.substring(0, txt.selectionstart), txt.font).height;
111 }
112 barv.maximum = inttxtmaxheight;
113 barv.value = (control as textbox).autoscrolloffset.y;
114 }
115 }
116 /// <summary>
117 /// resets the v scroll location.
118 /// </summary>
119 /// <param name="sender">the sender.</param>
120 private void resetvscrolllocation(object sender)
121 {
122 control control = (control)sender;
123 bool blnhasvscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & vscroll) != 0;
124 bool blnhashscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & hscroll) != 0;
125 if (control.visible)
126 {
127 if (m_lstvcache.containskey(control))
128 {
129 m_lstvcache[control].location = new system.drawing.point(control.right - m_lstvcache[control].width - 1, control.top + 1);
130 if (blnhashscrollbar)
131 {
132 m_lstvcache[control].height = control.height - m_lstvcache[control].width - 2;
133 }
134 else
135 {
136 m_lstvcache[control].height = control.height - 2;
137 }
138 }
139 }
140 }
141 /// <summary>
142 /// handles the visiblechanged event of the control control.
143 /// </summary>
144 /// <param name="sender">the source of the event.</param>
145 /// <param name="e">the <see cref="eventargs"/> instance containing the event data.</param>
146 void control_visiblechanged(object sender, eventargs e)
147 {
148 control control = (control)sender;
149 if (!control.visible)
150 {
151 if (m_lstvcache.containskey(control) && m_lstvcache[control].parent != null)
152 {
153 m_lstvcache[control].parent.controls.remove(m_lstvcache[control]);
154 m_lstvcache.remove(control);
155 }
156 }
157 }
158
159 private const int hscroll = 0x100000;
160 private const int vscroll = 0x200000;
161 private const int style = -16;
162
163 private dictionary<control, ucvscrollbar> m_lstvcache = new dictionary<control, ucvscrollbar>();
164 //private dictionary<scrollablecontrol, ucvscrollbar> m_lsthcache = new dictionary<scrollablecontrol, ucvscrollbar>();
165
166 void barv_scroll(object sender, eventargs e)
167 {
168 ucvscrollbar bar = (ucvscrollbar)sender;
169 if (m_lstvcache.containsvalue(bar))
170 {
171 control c = m_lstvcache.firstordefault(p => p.value == bar).key;
172 if (c is scrollablecontrol)
173 {
174 (c as scrollablecontrol).autoscrollposition = new point(0, bar.value);
175 }
176 else if (c is treeview)
177 {
178 treeview tv = (c as treeview);
179 settreeviewscrolllocation(tv, tv.nodes, bar.value);
180 }
181 else if (c is textbox)
182 {
183 textbox txt = (c as textbox);
184 settextboxscrolllocation(txt, bar.value);
185 }
186 }
187 }
188
189 #region treeview处理 english:treeview\u5904\u7406
190 void tv_aftercollapse(object sender, treevieweventargs e)
191 {
192 control_sizechanged(sender as control, null);
193 }
194
195 void tv_afterexpand(object sender, treevieweventargs e)
196 {
197 control_sizechanged(sender as control, null);
198 }
199 /// <summary>
200 /// gets the tree node 最大高度
201 /// </summary>
202 /// <param name="tv">the tv.</param>
203 /// <returns>system.int32.</returns>
204 private int gettreenodemaxy(treeview tv)
205 {
206 treenode tnlast = tv.nodes[tv.nodes.count - 1];
207 begin:
208 if (tnlast.isexpanded && tnlast.nodes.count > 0)
209 {
210 tnlast = tnlast.lastnode;
211 goto begin;
212 }
213 return tnlast.bounds.bottom;
214 }
215 void tv_afterselect(object sender, treevieweventargs e)
216 {
217 treeview tv = (treeview)sender;
218 if (m_lstvcache.containskey(tv))
219 {
220 m_lstvcache[tv].value = tv.nodes.count > 0 ? math.abs(tv.nodes[0].bounds.top) : 0;
221 }
222 }
223
224 void tv_mousewheel(object sender, mouseeventargs e)
225 {
226 treeview tv = (treeview)sender;
227 if (m_lstvcache.containskey(tv))
228 {
229 m_lstvcache[tv].value = tv.nodes.count > 0 ? math.abs(tv.nodes[0].bounds.top) : 0;
230 }
231 }
232 /// <summary>
233 /// sets the treeview scroll location.
234 /// </summary>
235 /// <param name="tv">the tv.</param>
236 /// <param name="tns">the tns.</param>
237 /// <param name="inty">the int y.</param>
238 /// <returns><c>true</c> if xxxx, <c>false</c> otherwise.</returns>
239 private bool settreeviewscrolllocation(treeview tv, treenodecollection tns, int inty)
240 {
241 for (int i = 0; i < tns.count; i++)
242 {
243 if (inty >= tns[i].bounds.top - tv.nodes[0].bounds.top - 3 && inty <= tns[i].bounds.bottom - tv.nodes[0].bounds.top + 3)
244 {
245 tns[i].ensurevisible();
246 return true;
247 }
248 else if (tns[i].isexpanded && tns[i].nodes.count > 0)
249 {
250 bool bln = settreeviewscrolllocation(tv, tns[i].nodes, inty);
251 if (bln)
252 return true;
253 }
254 }
255 return false;
256 }
257 #endregion
258
259 #region textbox处理 english:textbox processing
260
261 void txt_textchanged(object sender, eventargs e)
262 {
263 textbox txt = sender as textbox;
264 control_sizechanged(txt, null);
265 setvmaxnum(txt);
266 if (m_lstvcache.containskey(txt))
267 {
268 using (var g = txt.creategraphics())
269 {
270 var size = g.measurestring(txt.text.substring(0, txt.selectionstart), txt.font);
271 m_lstvcache[txt].value = (int)size.height;
272 }
273 }
274 }
275 private void settextboxscrolllocation(textbox txt, int inty)
276 {
277 using (var g = txt.creategraphics())
278 {
279 for (int i = 0; i < txt.lines.length; i++)
280 {
281 string str = string.join("\n", txt.lines.take(i + 1));
282 var size = g.measurestring(str, txt.font);
283 if (size.height >= inty)
284 {
285 txt.selectionstart = str.length;
286 txt.scrolltocaret();
287 return;
288 }
289 }
290 }
291 }
292
293 void txt_keydown(object sender, keyeventargs e)
294 {
295 if (e.keycode == keys.up || e.keycode == keys.down)
296 {
297 textbox txt = (textbox)sender;
298 if (m_lstvcache.containskey(txt))
299 {
300 using (var g = txt.creategraphics())
301 {
302 var size = g.measurestring(txt.text.substring(0, txt.selectionstart), txt.font);
303 m_lstvcache[txt].value = (int)size.height;
304 }
305 }
306 }
307 }
308
309 void txt_mousewheel(object sender, mouseeventargs e)
310 {
311 textbox txt = (textbox)sender;
312 if (m_lstvcache.containskey(txt))
313 {
314 using (var g = txt.creategraphics())
315 {
316 stringbuilder str = new stringbuilder();
317 for (int i = 0; i < system.windows.forms.systeminformation.mousewheelscrolllines; i++)
318 {
319 str.appendline("a");
320 }
321 var height = (int)g.measurestring(str.tostring(), txt.font).height;
322 if (e.delta < 0)
323 {
324 if (height + m_lstvcache[txt].value > m_lstvcache[txt].maximum)
325 m_lstvcache[txt].value = m_lstvcache[txt].maximum;
326 else
327 m_lstvcache[txt].value += height;
328 }
329 else
330 {
331 if (m_lstvcache[txt].value - height < 0)
332 m_lstvcache[txt].value = 0;
333 else
334 m_lstvcache[txt].value -= height;
335 }
336 }
337 }
338 }
339 #endregion
完整代码
1 using system;
2 using system.collections.generic;
3 using system.componentmodel;
4 using system.drawing;
5 using system.linq;
6 using system.text;
7 using system.windows.forms;
8
9 namespace hzh_controls.controls.scrollbar
10 {
11 [provideproperty("usercustomscrollbar", typeof(control))]
12 public class scrollbarcomponent : component, iextenderprovider
13 {
14 public scrollbarcomponent()
15 {
16 }
17
18 public scrollbarcomponent(icontainer container)
19 {
20 container.add(this);
21 }
22 bool m_blnusercustomscrollbar = true;
23 public bool canextend(object extendee)
24 {
25 if (extendee is scrollablecontrol)
26 {
27 scrollablecontrol control = (scrollablecontrol)extendee;
28 if (control.autoscroll == true)
29 {
30 return true;
31 }
32 }
33 else if (extendee is treeview)
34 {
35 treeview control = (treeview)extendee;
36 if (control.scrollable)
37 {
38 return true;
39 }
40 }
41 else if (extendee is textbox)
42 {
43 textbox control = (textbox)extendee;
44 if (control.multiline && control.scrollbars != scrollbars.none)
45 {
46 return true;
47 }
48 }
49 return false;
50 }
51
52 [browsable(true), category("自定义属性"), description("是否使用自定义滚动条"), displayname("usercustomscrollbar"), localizable(true)]
53 public bool getusercustomscrollbar(control control)
54 {
55 return m_blnusercustomscrollbar;
56 }
57
58 public void setusercustomscrollbar(control control, bool blnusercustomscrollbar)
59 {
60 m_blnusercustomscrollbar = blnusercustomscrollbar;
61 control.visiblechanged += control_visiblechanged;
62 control.sizechanged += control_sizechanged;
63 control.locationchanged += control_locationchanged;
64 control.disposed += control_disposed;
65
66 if (control is treeview)
67 {
68 treeview tv = (treeview)control;
69 tv.mousewheel += tv_mousewheel;
70 tv.afterselect += tv_afterselect;
71 tv.afterexpand += tv_afterexpand;
72 tv.aftercollapse += tv_aftercollapse;
73 }
74 else if (control is textbox)
75 {
76 textbox txt = (textbox)control;
77 txt.mousewheel += txt_mousewheel;
78 txt.textchanged += txt_textchanged;
79
80 txt.keydown += txt_keydown;
81 }
82 control_sizechanged(control, null);
83 }
84
85
86 void control_disposed(object sender, eventargs e)
87 {
88 control control = (control)sender;
89 if (m_lstvcache.containskey(control) && m_lstvcache[control].parent != null)
90 {
91 m_lstvcache[control].parent.controls.remove(m_lstvcache[control]);
92 m_lstvcache.remove(control);
93 }
94 }
95
96 void control_locationchanged(object sender, eventargs e)
97 {
98 resetvscrolllocation(sender);
99 }
100
101 void control_sizechanged(object sender, eventargs e)
102 {
103 if (controlhelper.isdesignmode())
104 {
105 return;
106 }
107 else
108 {
109 var control = sender as control;
110
111 bool blnhasvscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & vscroll) != 0;
112 bool blnhashscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & hscroll) != 0;
113 if (blnhasvscrollbar)
114 {
115 if (!m_lstvcache.containskey(control))
116 {
117 if (control.parent != null)
118 {
119 ucvscrollbar barv = new ucvscrollbar();
120 barv.scroll += barv_scroll;
121 m_lstvcache[control] = barv;
122 if (blnhashscrollbar)
123 {
124 barv.height = control.height - barv.width - 2;
125 }
126 else
127 {
128 barv.height = control.height - 2;
129 }
130 setvmaxnum(control);
131 barv.location = new system.drawing.point(control.right - barv.width - 1, control.top + 1);
132 control.parent.controls.add(barv);
133 int intcontrolindex = control.parent.controls.getchildindex(control);
134 control.parent.controls.setchildindex(barv, intcontrolindex);
135 }
136 }
137 else
138 {
139 setvmaxnum(control);
140 }
141 }
142 else
143 {
144 if (m_lstvcache.containskey(control) && m_lstvcache[control].parent != null)
145 {
146 m_lstvcache[control].parent.controls.remove(m_lstvcache[control]);
147 m_lstvcache.remove(control);
148 }
149 }
150
151 //if (blnhashscrollbar)
152 //{
153 // if (control.parent != null)
154 // {
155
156 // }
157 //}
158 //else
159 //{
160 // if (m_lsthcache.containskey(control))
161 // {
162 // if (m_lsthcache[control].visible)
163 // {
164 // m_lsthcache[control].parent.controls.remove(m_lsthcache[control]);
165 // }
166 // }
167 //}
168 }
169 resetvscrolllocation(sender);
170 }
171
172 private void setvmaxnum(control control)
173 {
174 if (!m_lstvcache.containskey(control))
175 return;
176 ucvscrollbar barv = m_lstvcache[control];
177 if (control is scrollablecontrol)
178 {
179 barv.maximum = (control as scrollablecontrol).verticalscroll.maximum;
180 barv.value = (control as scrollablecontrol).verticalscroll.value;
181 }
182 else if (control is treeview)
183 {
184 barv.maximum = gettreenodemaxy(control as treeview);
185 barv.value = (control as treeview).autoscrolloffset.y;
186 }
187 else if (control is textbox)
188 {
189 textbox txt = (textbox)control;
190 int inttxtmaxheight = 0;
191 int inttextheight = 0;
192 using (var g = txt.creategraphics())
193 {
194 inttxtmaxheight = (int)g.measurestring(txt.text, txt.font).height;
195 inttextheight = (int)g.measurestring(txt.text.substring(0, txt.selectionstart), txt.font).height;
196 }
197 barv.maximum = inttxtmaxheight;
198 barv.value = (control as textbox).autoscrolloffset.y;
199 }
200 }
201 /// <summary>
202 /// resets the v scroll location.
203 /// </summary>
204 /// <param name="sender">the sender.</param>
205 private void resetvscrolllocation(object sender)
206 {
207 control control = (control)sender;
208 bool blnhasvscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & vscroll) != 0;
209 bool blnhashscrollbar = control.ishandlecreated && (controlhelper.getwindowlong(control.handle, style) & hscroll) != 0;
210 if (control.visible)
211 {
212 if (m_lstvcache.containskey(control))
213 {
214 m_lstvcache[control].location = new system.drawing.point(control.right - m_lstvcache[control].width - 1, control.top + 1);
215 if (blnhashscrollbar)
216 {
217 m_lstvcache[control].height = control.height - m_lstvcache[control].width - 2;
218 }
219 else
220 {
221 m_lstvcache[control].height = control.height - 2;
222 }
223 }
224 }
225 }
226 /// <summary>
227 /// handles the visiblechanged event of the control control.
228 /// </summary>
229 /// <param name="sender">the source of the event.</param>
230 /// <param name="e">the <see cref="eventargs"/> instance containing the event data.</param>
231 void control_visiblechanged(object sender, eventargs e)
232 {
233 control control = (control)sender;
234 if (!control.visible)
235 {
236 if (m_lstvcache.containskey(control) && m_lstvcache[control].parent != null)
237 {
238 m_lstvcache[control].parent.controls.remove(m_lstvcache[control]);
239 m_lstvcache.remove(control);
240 }
241 }
242 }
243
244 private const int hscroll = 0x100000;
245 private const int vscroll = 0x200000;
246 private const int style = -16;
247
248 private dictionary<control, ucvscrollbar> m_lstvcache = new dictionary<control, ucvscrollbar>();
249 //private dictionary<scrollablecontrol, ucvscrollbar> m_lsthcache = new dictionary<scrollablecontrol, ucvscrollbar>();
250
251 void barv_scroll(object sender, eventargs e)
252 {
253 ucvscrollbar bar = (ucvscrollbar)sender;
254 if (m_lstvcache.containsvalue(bar))
255 {
256 control c = m_lstvcache.firstordefault(p => p.value == bar).key;
257 if (c is scrollablecontrol)
258 {
259 (c as scrollablecontrol).autoscrollposition = new point(0, bar.value);
260 }
261 else if (c is treeview)
262 {
263 treeview tv = (c as treeview);
264 settreeviewscrolllocation(tv, tv.nodes, bar.value);
265 }
266 else if (c is textbox)
267 {
268 textbox txt = (c as textbox);
269 settextboxscrolllocation(txt, bar.value);
270 }
271 }
272 }
273
274 #region treeview处理 english:treeview\u5904\u7406
275 void tv_aftercollapse(object sender, treevieweventargs e)
276 {
277 control_sizechanged(sender as control, null);
278 }
279
280 void tv_afterexpand(object sender, treevieweventargs e)
281 {
282 control_sizechanged(sender as control, null);
283 }
284 /// <summary>
285 /// gets the tree node 最大高度
286 /// </summary>
287 /// <param name="tv">the tv.</param>
288 /// <returns>system.int32.</returns>
289 private int gettreenodemaxy(treeview tv)
290 {
291 treenode tnlast = tv.nodes[tv.nodes.count - 1];
292 begin:
293 if (tnlast.isexpanded && tnlast.nodes.count > 0)
294 {
295 tnlast = tnlast.lastnode;
296 goto begin;
297 }
298 return tnlast.bounds.bottom;
299 }
300 void tv_afterselect(object sender, treevieweventargs e)
301 {
302 treeview tv = (treeview)sender;
303 if (m_lstvcache.containskey(tv))
304 {
305 m_lstvcache[tv].value = tv.nodes.count > 0 ? math.abs(tv.nodes[0].bounds.top) : 0;
306 }
307 }
308
309 void tv_mousewheel(object sender, mouseeventargs e)
310 {
311 treeview tv = (treeview)sender;
312 if (m_lstvcache.containskey(tv))
313 {
314 m_lstvcache[tv].value = tv.nodes.count > 0 ? math.abs(tv.nodes[0].bounds.top) : 0;
315 }
316 }
317 /// <summary>
318 /// sets the treeview scroll location.
319 /// </summary>
320 /// <param name="tv">the tv.</param>
321 /// <param name="tns">the tns.</param>
322 /// <param name="inty">the int y.</param>
323 /// <returns><c>true</c> if xxxx, <c>false</c> otherwise.</returns>
324 private bool settreeviewscrolllocation(treeview tv, treenodecollection tns, int inty)
325 {
326 for (int i = 0; i < tns.count; i++)
327 {
328 if (inty >= tns[i].bounds.top - tv.nodes[0].bounds.top - 3 && inty <= tns[i].bounds.bottom - tv.nodes[0].bounds.top + 3)
329 {
330 tns[i].ensurevisible();
331 return true;
332 }
333 else if (tns[i].isexpanded && tns[i].nodes.count > 0)
334 {
335 bool bln = settreeviewscrolllocation(tv, tns[i].nodes, inty);
336 if (bln)
337 return true;
338 }
339 }
340 return false;
341 }
342 #endregion
343
344 #region textbox处理 english:textbox processing
345
346 void txt_textchanged(object sender, eventargs e)
347 {
348 textbox txt = sender as textbox;
349 control_sizechanged(txt, null);
350 setvmaxnum(txt);
351 if (m_lstvcache.containskey(txt))
352 {
353 using (var g = txt.creategraphics())
354 {
355 var size = g.measurestring(txt.text.substring(0, txt.selectionstart), txt.font);
356 m_lstvcache[txt].value = (int)size.height;
357 }
358 }
359 }
360 private void settextboxscrolllocation(textbox txt, int inty)
361 {
362 using (var g = txt.creategraphics())
363 {
364 for (int i = 0; i < txt.lines.length; i++)
365 {
366 string str = string.join("\n", txt.lines.take(i + 1));
367 var size = g.measurestring(str, txt.font);
368 if (size.height >= inty)
369 {
370 txt.selectionstart = str.length;
371 txt.scrolltocaret();
372 return;
373 }
374 }
375 }
376 }
377
378 void txt_keydown(object sender, keyeventargs e)
379 {
380 if (e.keycode == keys.up || e.keycode == keys.down)
381 {
382 textbox txt = (textbox)sender;
383 if (m_lstvcache.containskey(txt))
384 {
385 using (var g = txt.creategraphics())
386 {
387 var size = g.measurestring(txt.text.substring(0, txt.selectionstart), txt.font);
388 m_lstvcache[txt].value = (int)size.height;
389 }
390 }
391 }
392 }
393
394 void txt_mousewheel(object sender, mouseeventargs e)
395 {
396 textbox txt = (textbox)sender;
397 if (m_lstvcache.containskey(txt))
398 {
399 using (var g = txt.creategraphics())
400 {
401 stringbuilder str = new stringbuilder();
402 for (int i = 0; i < system.windows.forms.systeminformation.mousewheelscrolllines; i++)
403 {
404 str.appendline("a");
405 }
406 var height = (int)g.measurestring(str.tostring(), txt.font).height;
407 if (e.delta < 0)
408 {
409 if (height + m_lstvcache[txt].value > m_lstvcache[txt].maximum)
410 m_lstvcache[txt].value = m_lstvcache[txt].maximum;
411 else
412 m_lstvcache[txt].value += height;
413 }
414 else
415 {
416 if (m_lstvcache[txt].value - height < 0)
417 m_lstvcache[txt].value = 0;
418 else
419 m_lstvcache[txt].value -= height;
420 }
421 }
422 }
423 }
424 #endregion
425 }
426 }
代码就这些了
使用的时候，只需要在界面上添加组件scrollbarcomponent即可
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