c# 模拟windows桌面鼠标拖选 张宇轩

命名空间
using System.Drawing;

定义两个变量
bool MouseIsDown=false;
Rectangle MouseRect   =   Rectangle.Empty;

定义三个方法
private void ResizeToRectangle(Point   p)
{
    DrawRectangle();
    MouseRect.Width = p.X - MouseRect.Left;
    MouseRect.Height = p.Y - MouseRect.Top;
    DrawRectangle();
}
private void DrawRectangle()
{
   Rectangle rect = this.RectangleToScreen(MouseRect);
   ControlPaint.DrawReversibleFrame(rect,Color.White,FrameStyle.Dashed);
}

private void DrawStart(Point StartPoint)
{
   this.Capture = true;
   Cursor.Clip = this.RectangleToScreen(this.Bounds);
   MouseRect = new Rectangle(StartPoint.X,StartPoint.Y,0,0);
}

在鼠标按下事件里写（一定是鼠标按下事件MouseDown   因为我的参数e是鼠标数据对象
（不过你也可以传坐标））
MouseIsDown = true;
DrawStart(e.Location);

在鼠标移动（MouseMove）事件里写    
if(MouseIsDown)
    ResizeToRectangle(e.Location);


在鼠标释放（MouseUp）事件里写      
this.Capture = false;
Cursor.Clip = Rectangle.Empty;
MouseIsDown = false;
DrawRectangle();
MouseRect = Rectangle.Empty;