（七十）c#Winform自定义控件-饼状图
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2022-05-18 17:13:50
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
准备工作
使用gdi+画的控件，不了解可以先百度下
开始
添加一个类ucpiechart ，继承usercontrol
添加一些属性
1 /// <summary>
2 /// the pie items
3 /// </summary>
4 private pieitem[] pieitems = new pieitem[0];
5
6 /// <summary>
7 /// the random
8 /// </summary>
9 private random random = null;
10
11 /// <summary>
12 /// the format center
13 /// </summary>
14 private stringformat formatcenter = null;
15
16 /// <summary>
17 /// the margin
18 /// </summary>
19 private int margin = 50;
20
21 /// <summary>
22 /// the m is render percent
23 /// </summary>
24 private bool m_isrenderpercent = false;
25
26 /// <summary>
27 /// the percen format
28 /// </summary>
29 private string percenformat = "{0:f2}%";
30
31 /// <summary>
32 /// the components
33 /// </summary>
34 private icontainer components = null;
35
36 /// <summary>
37 /// gets or sets a value indicating whether this instance is render percent.
38 /// </summary>
39 /// <value><c>true</c> if this instance is render percent; otherwise, <c>false</c>.</value>
40 [browsable(true)]
41 [category("自定义")]
42 [defaultvalue(false)]
43 [description("获取或设置是否显示百分比占用")]
44 public bool isrenderpercent
45 {
46 get
47 {
48 return m_isrenderpercent;
49 }
50 set
51 {
52 m_isrenderpercent = value;
53 invalidate();
54 }
55 }
56
57
58 /// <summary>
59 /// gets or sets the text margin.
60 /// </summary>
61 /// <value>the text margin.</value>
62 [browsable(true)]
63 [category("自定义")]
64 [description("获取或设置文本距离，单位为像素，默认50")]
65 [defaultvalue(50)]
66 public int textmargin
67 {
68 get
69 {
70 return margin;
71 }
72 set
73 {
74 margin = value;
75 invalidate();
76 }
77 }
78
79
80 /// <summary>
81 /// gets or sets the percent format.
82 /// </summary>
83 /// <value>the percent format.</value>
84 [browsable(true)]
85 [category("自定义")]
86 [description("获取或设置文百分比文字的格式化信息")]
87 [defaultvalue("{0:f2}%")]
88 public string percentformat
89 {
90 get
91 {
92 return percenformat;
93 }
94 set
95 {
96 percenformat = value;
97 invalidate();
98 }
99 }
100
101 /// <summary>
102 /// the center of circle color
103 /// </summary>
104 private color centerofcirclecolor = color.white;
105 /// <summary>
106 /// gets or sets the color of the center of circle.
107 /// </summary>
108 /// <value>the color of the center of circle.</value>
109 [browsable(true)]
110 [category("自定义")]
111 [description("获取或设置圆心颜色")]
112 public color centerofcirclecolor
113 {
114 get { return centerofcirclecolor; }
115 set
116 {
117 centerofcirclecolor = value;
118 invalidate();
119 }
120 }
121
122 /// <summary>
123 /// the center of circle width
124 /// </summary>
125 private int centerofcirclewidth = 0;
126 /// <summary>
127 /// gets or sets the width of the center of circle.
128 /// </summary>
129 /// <value>the width of the center of circle.</value>
130 [browsable(true)]
131 [category("自定义")]
132 [description("获取或设置圆心宽度")]
133 public int centerofcirclewidth
134 {
135 get { return centerofcirclewidth; }
136 set
137 {
138 if (value < 0)
139 return;
140 centerofcirclewidth = value;
141 invalidate();
142 }
143 }
144
145 /// <summary>
146 /// the title
147 /// </summary>
148 private string title;
149 /// <summary>
150 /// gets or sets the ti tle.
151 /// </summary>
152 /// <value>the ti tle.</value>
153 [browsable(true)]
154 [category("自定义")]
155 [description("获取或设置标题")]
156 public string title
157 {
158 get { return title; }
159 set
160 {
161 title = value;
162 resettitleheight();
163 invalidate();
164 }
165 }
166 /// <summary>
167 /// the title font
168 /// </summary>
169 private font titlefont = new font("微软雅黑", 12);
170 /// <summary>
171 /// gets or sets the title font.
172 /// </summary>
173 /// <value>the title font.</value>
174 [browsable(true)]
175 [category("自定义")]
176 [description("获取或设置标题字体")]
177 public font titlefont
178 {
179 get { return titlefont; }
180 set
181 {
182 titlefont = value;
183 resettitleheight();
184 invalidate();
185 }
186 }
187
188 /// <summary>
189 /// the title froe color
190 /// </summary>
191 private color titlefroecolor = color.black;
192 /// <summary>
193 /// gets or sets the color of the title froe.
194 /// </summary>
195 /// <value>the color of the title froe.</value>
196 [browsable(true)]
197 [category("自定义")]
198 [description("获取或设置标题颜色")]
199 public color titlefroecolor
200 {
201 get { return titlefroecolor; }
202 set
203 {
204 titlefroecolor = value;
205 invalidate();
206 }
207 }
208
209 /// <summary>
210 /// the title size
211 /// </summary>
212 private sizef titlesize = sizef.empty;
213 /// <summary>
214 /// resets the height of the title.
215 /// </summary>
216 private void resettitleheight()
217 {
218 if (string.isnullorempty(title))
219 titlesize = sizef.empty;
220 else
221 {
222 using (var g = this.creategraphics())
223 {
224 titlesize = g.measurestring(title, titlefont);
225 }
226 }
227 }
228
229 /// <summary>
230 /// gets or sets the data source.
231 /// </summary>
232 /// <value>the data source.</value>
233 [browsable(true)]
234 [category("自定义")]
235 [description("获取或设置标题颜色")]
236 [localizable(true)]
237 public pieitem[] datasource
238 {
239 get { return pieitems; }
240 set
241 {
242 pieitems = value;
243 invalidate();
244 }
245 }
重绘
1 protected override void onpaint(painteventargs e)
2 {
3 e.graphics.setgdihigh();
4
5 int width;
6 point centerpoint = getcenterpoint(out width);
7 rectangle rectangle = new rectangle(centerpoint.x - width, centerpoint.y - width, width * 2, width * 2);
8 if (width > 0 && pieitems.length != 0)
9 {
10 if (!string.isnullorempty(title))
11 e.graphics.drawstring(title, titlefont, new solidbrush(titlefroecolor), new pointf((this.width - titlesize.width) / 2, 5));
12 rectangle rect = new rectangle(rectangle.x - centerpoint.x, rectangle.y - centerpoint.y, rectangle.width, rectangle.height);
13 e.graphics.translatetransform(centerpoint.x, centerpoint.y);
14 e.graphics.rotatetransform(90f);
15 int num = pieitems.sum((pieitem item) => item.value);
16 float num2 = 0f;
17 float num3 = -90f;
18 for (int i = 0; i < pieitems.length; i++)
19 {
20 color citem = pieitems[i].piecolor ?? controlhelper.colors[i];
21 pen pen = new pen(citem, 1f);
22 solidbrush solidbrush = new solidbrush(citem);
23 solidbrush solidbrush2 = new solidbrush(citem);
24 brush percentbrush = new solidbrush(citem);
25 float num4 = e.graphics.measurestring(pieitems[i].name, font).width + 3f;
26 float num5 = (num != 0) ? convert.tosingle((double)pieitems[i].value * 1.0 / (double)num * 360.0) : ((float)(360 / pieitems.length));
27 e.graphics.fillpie(solidbrush, rect, 0f, 0f - num5);
28 e.graphics.drawpie(new pen(solidbrush), rect, 0f, 0f - num5);
29 e.graphics.rotatetransform(0f - num5 / 2f);
30 if (num5 < 2f)
31 {
32 num2 += num5;
33 }
34 else
35 {
36 num2 += num5 / 2f;
37 int num6 = 15;
38 if (num2 < 45f || num2 > 315f)
39 {
40 num6 = 20;
41 }
42 if (num2 > 135f && num2 < 225f)
43 {
44 num6 = 20;
45 }
46 e.graphics.drawline(pen, width * 2 / 3, 0, width + num6, 0);
47 e.graphics.translatetransform(width + num6, 0f);
48 if (num2 - num3 < 5f)
49 {
50 }
51 num3 = num2;
52 if (num2 < 180f)
53 {
54 e.graphics.rotatetransform(num2 - 90f);
55 e.graphics.drawline(pen, 0f, 0f, num4, 0f);
56 e.graphics.drawstring(pieitems[i].name, font, solidbrush2, new point(0, -font.height));
57 if (isrenderpercent)
58 {
59 e.graphics.drawstring(string.format(percenformat, num5 * 100f / 360f), font, percentbrush, new point(0, 1));
60 }
61 e.graphics.rotatetransform(90f - num2);
62 }
63 else
64 {
65 e.graphics.rotatetransform(num2 - 270f);
66 e.graphics.drawline(pen, 0f, 0f, num4, 0f);
67 e.graphics.translatetransform(num4 - 3f, 0f);
68 e.graphics.rotatetransform(180f);
69 e.graphics.drawstring(pieitems[i].name, font, solidbrush2, new point(0, -font.height));
70 if (isrenderpercent)
71 {
72 e.graphics.drawstring(string.format(percenformat, num5 * 100f / 360f), font, percentbrush, new point(0, 1));
73 }
74 e.graphics.rotatetransform(-180f);
75 e.graphics.translatetransform(0f - num4 + 3f, 0f);
76 e.graphics.rotatetransform(270f - num2);
77 }
78 e.graphics.translatetransform(-width - num6, 0f);
79 e.graphics.rotatetransform(0f - num5 / 2f);
80 num2 += num5 / 2f;
81 }
82 solidbrush.dispose();
83 pen.dispose();
84 solidbrush2.dispose();
85 percentbrush.dispose();
86 }
87 e.graphics.resettransform();
88
89 if (centerofcirclewidth > 0)
90 {
91 rectangle rectcenter = new rectangle(rect.left + rect.width / 2 - centerofcirclewidth / 2, rect.top + rect.height / 2 - centerofcirclewidth / 2, centerofcirclewidth, centerofcirclewidth);
92 e.graphics.fillellipse(new solidbrush(centerofcirclecolor), rectcenter);
93 }
94 }
95 else
96 {
97 e.graphics.fillellipse(brushes.aliceblue, rectangle);
98 e.graphics.drawellipse(pens.dodgerblue, rectangle);
99 e.graphics.drawstring("无数据", font, brushes.dimgray, rectangle, formatcenter);
100 }
101 base.onpaint(e);
102 }
一些辅助函数
1 /// <summary>
2 /// sets the data source.
3 /// </summary>
4 /// <param name="source">the source.</param>
5 public void setdatasource(pieitem[] source)
6 {
7 if (source != null)
8 {
9 datasource = source;
10 }
11 }
12 /// <summary>
13 /// sets the data source.
14 /// </summary>
15 /// <param name="names">the names.</param>
16 /// <param name="values">the values.</param>
17 /// <exception cref="system.argumentnullexception">
18 /// names
19 /// or
20 /// values
21 /// </exception>
22 /// <exception cref="system.exception">两个数组的长度不一致！</exception>
23 public void setdatasource(string[] names, int[] values)
24 {
25 if (names == null)
26 {
27 throw new argumentnullexception("names");
28 }
29 if (values == null)
30 {
31 throw new argumentnullexception("values");
32 }
33 if (names.length != values.length)
34 {
35 throw new exception("两个数组的长度不一致！");
36 }
37 pieitems = new pieitem[names.length];
38 for (int i = 0; i < names.length; i++)
39 {
40 pieitems[i] = new pieitem
41 {
42 name = names[i],
43 value = values[i]
44 };
45 }
46 invalidate();
47 }
完整代码
1 // ***********************************************************************
2 // assembly : hzh_controls
3 // created : 2019-09-23
4 //
5 // ***********************************************************************
6 // <copyright file="ucpiechart.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.componentmodel;
18 using system.componentmodel.design;
19 using system.drawing;
20 using system.drawing.drawing2d;
21 using system.drawing.text;
22 using system.linq;
23 using system.windows.forms;
24
25 namespace hzh_controls.controls
26 {
27 /// <summary>
28 /// class ucpiechart.
29 /// implements the <see cref="system.windows.forms.usercontrol" />
30 /// </summary>
31 /// <seealso cref="system.windows.forms.usercontrol" />
32 public class ucpiechart : usercontrol
33 {
34 /// <summary>
35 /// the pie items
36 /// </summary>
37 private pieitem[] pieitems = new pieitem[0];
38
39 /// <summary>
40 /// the random
41 /// </summary>
42 private random random = null;
43
44 /// <summary>
45 /// the format center
46 /// </summary>
47 private stringformat formatcenter = null;
48
49 /// <summary>
50 /// the margin
51 /// </summary>
52 private int margin = 50;
53
54 /// <summary>
55 /// the m is render percent
56 /// </summary>
57 private bool m_isrenderpercent = false;
58
59 /// <summary>
60 /// the percen format
61 /// </summary>
62 private string percenformat = "{0:f2}%";
63
64 /// <summary>
65 /// the components
66 /// </summary>
67 private icontainer components = null;
68
69 /// <summary>
70 /// gets or sets a value indicating whether this instance is render percent.
71 /// </summary>
72 /// <value><c>true</c> if this instance is render percent; otherwise, <c>false</c>.</value>
73 [browsable(true)]
74 [category("自定义")]
75 [defaultvalue(false)]
76 [description("获取或设置是否显示百分比占用")]
77 public bool isrenderpercent
78 {
79 get
80 {
81 return m_isrenderpercent;
82 }
83 set
84 {
85 m_isrenderpercent = value;
86 invalidate();
87 }
88 }
89
90
91 /// <summary>
92 /// gets or sets the text margin.
93 /// </summary>
94 /// <value>the text margin.</value>
95 [browsable(true)]
96 [category("自定义")]
97 [description("获取或设置文本距离，单位为像素，默认50")]
98 [defaultvalue(50)]
99 public int textmargin
100 {
101 get
102 {
103 return margin;
104 }
105 set
106 {
107 margin = value;
108 invalidate();
109 }
110 }
111
112
113 /// <summary>
114 /// gets or sets the percent format.
115 /// </summary>
116 /// <value>the percent format.</value>
117 [browsable(true)]
118 [category("自定义")]
119 [description("获取或设置文百分比文字的格式化信息")]
120 [defaultvalue("{0:f2}%")]
121 public string percentformat
122 {
123 get
124 {
125 return percenformat;
126 }
127 set
128 {
129 percenformat = value;
130 invalidate();
131 }
132 }
133
134 /// <summary>
135 /// the center of circle color
136 /// </summary>
137 private color centerofcirclecolor = color.white;
138 /// <summary>
139 /// gets or sets the color of the center of circle.
140 /// </summary>
141 /// <value>the color of the center of circle.</value>
142 [browsable(true)]
143 [category("自定义")]
144 [description("获取或设置圆心颜色")]
145 public color centerofcirclecolor
146 {
147 get { return centerofcirclecolor; }
148 set
149 {
150 centerofcirclecolor = value;
151 invalidate();
152 }
153 }
154
155 /// <summary>
156 /// the center of circle width
157 /// </summary>
158 private int centerofcirclewidth = 0;
159 /// <summary>
160 /// gets or sets the width of the center of circle.
161 /// </summary>
162 /// <value>the width of the center of circle.</value>
163 [browsable(true)]
164 [category("自定义")]
165 [description("获取或设置圆心宽度")]
166 public int centerofcirclewidth
167 {
168 get { return centerofcirclewidth; }
169 set
170 {
171 if (value < 0)
172 return;
173 centerofcirclewidth = value;
174 invalidate();
175 }
176 }
177
178 /// <summary>
179 /// the title
180 /// </summary>
181 private string title;
182 /// <summary>
183 /// gets or sets the ti tle.
184 /// </summary>
185 /// <value>the ti tle.</value>
186 [browsable(true)]
187 [category("自定义")]
188 [description("获取或设置标题")]
189 public string title
190 {
191 get { return title; }
192 set
193 {
194 title = value;
195 resettitleheight();
196 invalidate();
197 }
198 }
199 /// <summary>
200 /// the title font
201 /// </summary>
202 private font titlefont = new font("微软雅黑", 12);
203 /// <summary>
204 /// gets or sets the title font.
205 /// </summary>
206 /// <value>the title font.</value>
207 [browsable(true)]
208 [category("自定义")]
209 [description("获取或设置标题字体")]
210 public font titlefont
211 {
212 get { return titlefont; }
213 set
214 {
215 titlefont = value;
216 resettitleheight();
217 invalidate();
218 }
219 }
220
221 /// <summary>
222 /// the title froe color
223 /// </summary>
224 private color titlefroecolor = color.black;
225 /// <summary>
226 /// gets or sets the color of the title froe.
227 /// </summary>
228 /// <value>the color of the title froe.</value>
229 [browsable(true)]
230 [category("自定义")]
231 [description("获取或设置标题颜色")]
232 public color titlefroecolor
233 {
234 get { return titlefroecolor; }
235 set
236 {
237 titlefroecolor = value;
238 invalidate();
239 }
240 }
241
242 /// <summary>
243 /// the title size
244 /// </summary>
245 private sizef titlesize = sizef.empty;
246 /// <summary>
247 /// resets the height of the title.
248 /// </summary>
249 private void resettitleheight()
250 {
251 if (string.isnullorempty(title))
252 titlesize = sizef.empty;
253 else
254 {
255 using (var g = this.creategraphics())
256 {
257 titlesize = g.measurestring(title, titlefont);
258 }
259 }
260 }
261
262 /// <summary>
263 /// gets or sets the data source.
264 /// </summary>
265 /// <value>the data source.</value>
266 [browsable(true)]
267 [category("自定义")]
268 [description("获取或设置标题颜色")]
269 [localizable(true)]
270 public pieitem[] datasource
271 {
272 get { return pieitems; }
273 set
274 {
275 pieitems = value;
276 invalidate();
277 }
278 }
279
280 /// <summary>
281 /// initializes a new instance of the <see cref="ucpiechart"/> class.
282 /// </summary>
283 public ucpiechart()
284 {
285 initializecomponent();
286 random = new random();
287 formatcenter = new stringformat();
288 formatcenter.alignment = stringalignment.center;
289 formatcenter.linealignment = stringalignment.center;
290 setstyle(controlstyles.userpaint | controlstyles.supportstransparentbackcolor, true);
291 setstyle(controlstyles.resizeredraw, true);
292 setstyle(controlstyles.optimizeddoublebuffer, true);
293 setstyle(controlstyles.allpaintinginwmpaint, true);
294 pieitems = new pieitem[0];
295 if (getservice(typeof(idesignerhost)) != null || licensemanager.usagemode == licenseusagemode.designtime)
296 {
297 pieitems = new pieitem[5];
298
299 for (int i = 0; i < 5; i++)
300 {
301 pieitems[i] = new pieitem
302 {
303 name = "source" + (i + 1),
304 value = random.next(10, 100)
305 };
306 }
307 }
308 }
309
310
311
312 /// <summary>
313 /// gets the center point.
314 /// </summary>
315 /// <param name="width">the width.</param>
316 /// <returns>point.</returns>
317 private point getcenterpoint(out int width)
318 {
319 width = math.min(base.width, base.height - (titlesize != sizef.empty ? ((int)titlesize.height) : 0)) / 2 - margin - 8;
320 return new point(base.width / 2 - 1, base.height / 2 + (titlesize != sizef.empty ? ((int)titlesize.height) : 0) - 1);
321 }
322
323
324 /// <summary>
325 /// 引发 <see cref="e:system.windows.forms.control.paint" /> 事件。
326 /// </summary>
327 /// <param name="e">包含事件数据的 <see cref="t:system.windows.forms.painteventargs" />。</param>
328 protected override void onpaint(painteventargs e)
329 {
330 e.graphics.setgdihigh();
331
332 int width;
333 point centerpoint = getcenterpoint(out width);
334 rectangle rectangle = new rectangle(centerpoint.x - width, centerpoint.y - width, width * 2, width * 2);
335 if (width > 0 && pieitems.length != 0)
336 {
337 if (!string.isnullorempty(title))
338 e.graphics.drawstring(title, titlefont, new solidbrush(titlefroecolor), new pointf((this.width - titlesize.width) / 2, 5));
339 rectangle rect = new rectangle(rectangle.x - centerpoint.x, rectangle.y - centerpoint.y, rectangle.width, rectangle.height);
340 e.graphics.translatetransform(centerpoint.x, centerpoint.y);
341 e.graphics.rotatetransform(90f);
342 int num = pieitems.sum((pieitem item) => item.value);
343 float num2 = 0f;
344 float num3 = -90f;
345 for (int i = 0; i < pieitems.length; i++)
346 {
347 color citem = pieitems[i].piecolor ?? controlhelper.colors[i];
348 pen pen = new pen(citem, 1f);
349 solidbrush solidbrush = new solidbrush(citem);
350 solidbrush solidbrush2 = new solidbrush(citem);
351 brush percentbrush = new solidbrush(citem);
352 float num4 = e.graphics.measurestring(pieitems[i].name, font).width + 3f;
353 float num5 = (num != 0) ? convert.tosingle((double)pieitems[i].value * 1.0 / (double)num * 360.0) : ((float)(360 / pieitems.length));
354 e.graphics.fillpie(solidbrush, rect, 0f, 0f - num5);
355 e.graphics.drawpie(new pen(solidbrush), rect, 0f, 0f - num5);
356 e.graphics.rotatetransform(0f - num5 / 2f);
357 if (num5 < 2f)
358 {
359 num2 += num5;
360 }
361 else
362 {
363 num2 += num5 / 2f;
364 int num6 = 15;
365 if (num2 < 45f || num2 > 315f)
366 {
367 num6 = 20;
368 }
369 if (num2 > 135f && num2 < 225f)
370 {
371 num6 = 20;
372 }
373 e.graphics.drawline(pen, width * 2 / 3, 0, width + num6, 0);
374 e.graphics.translatetransform(width + num6, 0f);
375 if (num2 - num3 < 5f)
376 {
377 }
378 num3 = num2;
379 if (num2 < 180f)
380 {
381 e.graphics.rotatetransform(num2 - 90f);
382 e.graphics.drawline(pen, 0f, 0f, num4, 0f);
383 e.graphics.drawstring(pieitems[i].name, font, solidbrush2, new point(0, -font.height));
384 if (isrenderpercent)
385 {
386 e.graphics.drawstring(string.format(percenformat, num5 * 100f / 360f), font, percentbrush, new point(0, 1));
387 }
388 e.graphics.rotatetransform(90f - num2);
389 }
390 else
391 {
392 e.graphics.rotatetransform(num2 - 270f);
393 e.graphics.drawline(pen, 0f, 0f, num4, 0f);
394 e.graphics.translatetransform(num4 - 3f, 0f);
395 e.graphics.rotatetransform(180f);
396 e.graphics.drawstring(pieitems[i].name, font, solidbrush2, new point(0, -font.height));
397 if (isrenderpercent)
398 {
399 e.graphics.drawstring(string.format(percenformat, num5 * 100f / 360f), font, percentbrush, new point(0, 1));
400 }
401 e.graphics.rotatetransform(-180f);
402 e.graphics.translatetransform(0f - num4 + 3f, 0f);
403 e.graphics.rotatetransform(270f - num2);
404 }
405 e.graphics.translatetransform(-width - num6, 0f);
406 e.graphics.rotatetransform(0f - num5 / 2f);
407 num2 += num5 / 2f;
408 }
409 solidbrush.dispose();
410 pen.dispose();
411 solidbrush2.dispose();
412 percentbrush.dispose();
413 }
414 e.graphics.resettransform();
415
416 if (centerofcirclewidth > 0)
417 {
418 rectangle rectcenter = new rectangle(rect.left + rect.width / 2 - centerofcirclewidth / 2, rect.top + rect.height / 2 - centerofcirclewidth / 2, centerofcirclewidth, centerofcirclewidth);
419 e.graphics.fillellipse(new solidbrush(centerofcirclecolor), rectcenter);
420 }
421 }
422 else
423 {
424 e.graphics.fillellipse(brushes.aliceblue, rectangle);
425 e.graphics.drawellipse(pens.dodgerblue, rectangle);
426 e.graphics.drawstring("无数据", font, brushes.dimgray, rectangle, formatcenter);
427 }
428 base.onpaint(e);
429 }
430 /// <summary>
431 /// sets the data source.
432 /// </summary>
433 /// <param name="source">the source.</param>
434 public void setdatasource(pieitem[] source)
435 {
436 if (source != null)
437 {
438 datasource = source;
439 }
440 }
441 /// <summary>
442 /// sets the data source.
443 /// </summary>
444 /// <param name="names">the names.</param>
445 /// <param name="values">the values.</param>
446 /// <exception cref="system.argumentnullexception">
447 /// names
448 /// or
449 /// values
450 /// </exception>
451 /// <exception cref="system.exception">两个数组的长度不一致！</exception>
452 public void setdatasource(string[] names, int[] values)
453 {
454 if (names == null)
455 {
456 throw new argumentnullexception("names");
457 }
458 if (values == null)
459 {
460 throw new argumentnullexception("values");
461 }
462 if (names.length != values.length)
463 {
464 throw new exception("两个数组的长度不一致！");
465 }
466 pieitems = new pieitem[names.length];
467 for (int i = 0; i < names.length; i++)
468 {
469 pieitems[i] = new pieitem
470 {
471 name = names[i],
472 value = values[i]
473 };
474 }
475 invalidate();
476 }
477
478 /// <summary>
479 /// releases unmanaged and - optionally - managed resources.
480 /// </summary>
481 /// <param name="disposing">为 true 则释放托管资源和非托管资源；为 false 则仅释放非托管资源。</param>
482 protected override void dispose(bool disposing)
483 {
484 if (disposing && components != null)
485 {
486 components.dispose();
487 }
488 base.dispose(disposing);
489 }
490
491 /// <summary>
492 /// initializes the component.
493 /// </summary>
494 private void initializecomponent()
495 {
496 suspendlayout();
497 base.autoscalemode = system.windows.forms.autoscalemode.none;
498 backcolor = system.drawing.color.transparent;
499 base.name = "ucpiechart";
500 resumelayout(false);
501 }
502 }
503 }
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