【WinForm】运行时模仿窗体设计调整控件大小和位置

分析

我们先来看看，窗体设计时的控件样式

点击控件时会显示4条虚线和8个小矩形，但是同时我们为了绘制虚线和矩形，需要多设置4条底边

移动控件时会显示4条实线

 

实现运行时调整控件大小和位置，只需为控件绑定MouseDown，MouseClick，MouseMove，MouseUp事件即可
MouseDown：鼠标键按下时，显示灰色实线
MouseClick：鼠标单击时，显示4条虚线和8个小矩形
MouseMove：鼠标拖动控件时，显示灰色实线，当鼠标点击控件时也会执行该事件
MouseUp：鼠标键释放时，显示4条虚线和8个小矩形

我们可以用GDI+绘图技术，绘制控件的灰色实线和虚线

我们先制作边框控件，只需绑定MouseDown，MouseMove，MouseUp事件即可
MouseDown：鼠标键按下时，记录当前鼠标位置
MouseMove：鼠标在控件上移动时，移动时刷新4条灰色实线，改变鼠标光标并调整控件大小
MouseUp：鼠标键释放时，刷新4条虚线
边框控件包含边框的4条底边，4条灰色实线，4条虚线和8个小矩形

 

制作边框控件

边框控件首先需要继承UserControl

绑定MouseDown，MouseMove，MouseUp事件

接下来编写几个重要的方法

• 绘制实线：4条实线，移动控件和调整控件大小时显示
• 绘制虚线：包含4条底边，4条虚线和8个小矩形，点击控件后显示
• 改变鼠标状态：鼠标在控件上，下，左，右，左上，右上，左下，右下，向上不同的光标
• 调整控件大小：鼠标在控件中的不同位置，调整控件大小

 

绘制实线

绘制实线前，需要将隐藏边框（即是4条底边，4条虚线和8个小矩形）

public void DrawSolids()
{
    Visible = false;

    Graphics g = control.CreateGraphics();
    int width = control.Width;
    int height = control.Height;
    Point[] points = new Point[5] { new Point(0,0),new Point(width - 1,0),
                new Point(width - 1,height-1),new Point(0,height-1),new Point(0,0)};
    g.DrawLines(new Pen(Color.Gray, 3), points);
}

绘制虚线

绘制虚线前，需要将显示边框，在绘制4条底边，4条虚线和8个小矩形

public void DrawDottedLines()
{
    Visible = true;

    #region 设置控件区域

    BringToFront();

    int x = control.Bounds.X - smallRectSize.Width;
    int y = control.Bounds.Y - smallRectSize.Height;
    int width = control.Bounds.Width + (smallRectSize.Width * 2);
    int height = control.Bounds.Height + (smallRectSize.Height * 2);
    Bounds = new Rectangle(x, y, width, height);

    //包括边框的局域
    controlRect = new Rectangle(new Point(0, 0), Bounds.Size);

    Graphics g = CreateGraphics();
    g.Clear(control.Parent.BackColor);//清除之前绘制的

    #endregion

    #region 4条底边

    GraphicsPath path = new GraphicsPath();

    //上底边
    borderRects[0] = new Rectangle(0, 0, Width + size * 2, smallRectSize.Height + 1);
    //左底边
    borderRects[1] = new Rectangle(0, size + 1, smallRectSize.Width + 1, Height - size * 2 - 2);
    //下底边
    borderRects[2] = new Rectangle(0, Height - size - 1, Width + size * 2, smallRectSize.Height + 1);
    //右底边
    borderRects[3] = new Rectangle(Width - size - 1, size + 1, smallRectSize.Width + 1, Height - size * 2 - 2);
    path.AddRectangle(borderRects[0]);
    path.AddRectangle(borderRects[1]);
    path.AddRectangle(borderRects[2]);
    path.AddRectangle(borderRects[3]);

    Region = new Region(path);

    #endregion

    #region 4条虚线

    //左上
    linePoints[0] = new Point(3, 3);
    //右上
    linePoints[1] = new Point(Width - 3 - 1, 3);
    //右下
    linePoints[2] = new Point(Width - 3 - 1, Height - 3 - 1);
    //左下
    linePoints[3] = new Point(3, Height - 3 - 1);
    //左上
    linePoints[4] = new Point(3, 3);

    Pen pen = new Pen(Color.Black, 1) { DashStyle = DashStyle.Dot };

    g.DrawLines(pen, linePoints);

    #endregion

    #region  8个小矩形

    //左上
    smallRects[0] = new Rectangle(new Point(0, 0), smallRectSize);
    //右上
    smallRects[1] = new Rectangle(new Point(Width - size - 1, 0), smallRectSize);
    //左下
    smallRects[2] = new Rectangle(new Point(0, Height - size - 1), smallRectSize);
    //右下
    smallRects[3] = new Rectangle(new Point(Width - size - 1, Height - size - 1), smallRectSize);
    //上中
    smallRects[4] = new Rectangle(new Point(Width / 2 - 1, 0), smallRectSize);
    //下中
    smallRects[5] = new Rectangle(new Point(Width / 2 - 1, Height - size - 1), smallRectSize);
    //左中
    smallRects[6] = new Rectangle(new Point(0, Height / 2 - size / 2), smallRectSize);
    //右中
    smallRects[7] = new Rectangle(new Point(Width - size - 1, Height / 2 - size / 2), smallRectSize);

    //填充矩形内部为白色
    g.FillRectangles(Brushes.White, smallRects);
    //绘制矩形
    g.DrawRectangles(Pens.Black, smallRects);

    #endregion
}

改变鼠标状态

先定义一个枚举，存储鼠标在控件中的位置

enum MousePos
{
    None,
    Top,
    Right,
    Bottom,
    Left,
    LeftTop,
    LeftBottom,
    RightTop,
    RightBottom
}

根据鼠标在控件中的不同位置，改变鼠标状态

private void SetCursor(int x, int y)
{
    Point point = new Point(x, y);

    if (!controlRect.Contains(point))//不在边框局域内直接退出
    {
        Cursor.Current = Cursors.Arrow;
        return;
    }
    else
    if (smallRects[0].Contains(point))//左上
    {
        Cursor.Current = Cursors.SizeNWSE;
        mousePos = MousePos.LeftTop;
    }
    else if (smallRects[1].Contains(point))//右上
    {
        Cursor.Current = Cursors.SizeNESW;
        mousePos = MousePos.RightTop;
    }
    else if (smallRects[2].Contains(point))//左下
    {
        Cursor.Current = Cursors.SizeNESW;
        mousePos = MousePos.LeftBottom;
    }
    else if (smallRects[3].Contains(point))//右下
    {
        Cursor.Current = Cursors.SizeNWSE;
        mousePos = MousePos.RightBottom;
    }

    else if (borderRects[0].Contains(point))//上
    {
        Cursor.Current = Cursors.SizeNS;
        mousePos = MousePos.Top;
    }
    else if (borderRects[1].Contains(point))//左
    {
        Cursor.Current = Cursors.SizeWE;
        mousePos = MousePos.Left;
    }
    else if (borderRects[2].Contains(point))//下
    {
        Cursor.Current = Cursors.SizeNS;
        mousePos = MousePos.Bottom;
    }
    else if (borderRects[3].Contains(point))//右
    {
        Cursor.Current = Cursors.SizeWE;
        mousePos = MousePos.Right;
    }
    else
    {
        Cursor.Current = Cursors.Arrow;
    }
}

调整控件大小

比如，当鼠标处于控件的下方时，调整控件的Height属性即可

 

写成扩展方法，方便使用

public static partial class Extensions
{
    /// <summary>
    /// 为控件绑定事件
    /// </summary>
    /// <param name="control"></param>
    public static void SetMove(this Control control)
    {
        FrameControl fControl = null;//边框控件
        Point lPoint = new Point();//上一个鼠标坐标
        Point cPoint = new Point();//当前鼠标坐标

        #region 绑定事件

        //鼠标键按下时
        control.MouseDown += (sender, e) =>
        {
            //记录当前鼠标坐标
            lPoint = Cursor.Position;

            //清除所有控件的边框区域，最主要的是清除上次点击控件的边框，恢复原来状态
            foreach (Control ctrl in control.Parent.Controls)
                if (ctrl is FrameControl)
                    ctrl.Visible = false;

            fControl = new FrameControl(control);
            control.Parent.Controls.Add(fControl);
        };

        //鼠标单击时
        control.MouseClick += (sender, e) =>
        {
            control.BringToFront();
        };

        //鼠标在控件上移动时
        control.MouseMove += (sender, e) =>
        {
            Cursor.Current = Cursors.SizeAll;
            if (e.Button == MouseButtons.Left)
            {
                cPoint = Cursor.Position;
                control.Location = new Point(control.Location.X + cPoint.X - lPoint.X,
                    control.Location.Y + cPoint.Y - lPoint.Y);

                //移动时刷新实线
                fControl.DrawSolids();

                control.BringToFront();
            }

            lPoint = cPoint;
        };

        //鼠标键释放时
        control.MouseUp += (sender, e) =>
        {
            //显示虚线
            fControl.DrawDottedLines();
        };

        #endregion
    }
}

 

实现很简单，只需一句代码

button1.SetMove();

在运行时的效果

 

本文参考了网上的一些资料，自己并做了调整，使在运行时调整控件大小更像窗体设计的

但同时存在一个小问题，就是在调整控件大小时，鼠标光标会变成默认状态，虽然问题不大，但是也是个问题

 

源码下载：

WinForm运行时模仿窗体设计调整控件大小和位置源码