C＃ WinForm 控件的拖动和缩放技术全解

C＃ WinForm 控件的拖动和缩放技术全解

很简单的，主要是设计控件的MouseDown、MouseLeave、MouseMove事件。：
1、定义一个枚举类型，描述光标状态
private enum EnumMousePointPosition
   {
    MouseSizeNone   = 0, //'无
    MouseSizeRight   = 1, //'拉伸右边框
    MouseSizeLeft   = 2, //'拉伸左边框
    MouseSizeBottom   = 3, //'拉伸下边框
    MouseSizeTop   = 4, //'拉伸上边框
    MouseSizeTopLeft = 5, //'拉伸左上角
    MouseSizeTopRight = 6, //'拉伸右上角
    MouseSizeBottomLeft = 7, //'拉伸左下角
    MouseSizeBottomRight= 8, //'拉伸右下角
    MouseDrag    = 9   // '鼠标拖动
   }
2、定义几个变量
const int Band = 5;
   const int MinWidth=10;
   const int MinHeight=10;
   private EnumMousePointPosition m_MousePointPosition;
   private Point p,p1;

3、定义自己的MyMouseDown事件
   private void MyMouseDown(object sender,System.Windows.Forms.MouseEventArgs e)
   {
    p.X=e.X;
    p.Y=e.Y;

    p1.X=e.X;
    p1.Y=e.Y;   
   }

4、定义自己的MyMouseLeave事件
   private void MyMouseLeave(object sender, System.EventArgs e)
   {
    m_MousePointPosition = EnumMousePointPosition.MouseSizeNone;
    this.Cursor=Cursors.Arrow;
   }

5、设计一个函数，确定光标在控件不同位置的样式
   private EnumMousePointPosition MousePointPosition(Size size,System.Windows.Forms.MouseEventArgs e)
   {
   
    if ((e.X >= -1 * Band) | (e.X <= size.Width) | (e.Y >= -1 * Band) | (e.Y <= size.Height))
    {
     if (e.X < Band)
     {
      if (e.Y < Band) {return EnumMousePointPosition.MouseSizeTopLeft;}
      else
      {
       if (e.Y > -1 * Band + size.Height)
       {return EnumMousePointPosition.MouseSizeBottomLeft;}
       else
       {return EnumMousePointPosition.MouseSizeLeft;}
      }
     }
     else
     {
      if (e.X > -1 * Band + size.Width)
      {
       if (e.Y < Band)
       {return EnumMousePointPosition.MouseSizeTopRight;}
       else
       {
        if (e.Y > -1 * Band + size.Height)
        {return EnumMousePointPosition.MouseSizeBottomRight;}
        else
        {return EnumMousePointPosition.MouseSizeRight;}
       }
      }
      else
      {
       if (e.Y < Band)
       {return EnumMousePointPosition.MouseSizeTop;}
       else
       {
        if (e.Y > -1 * Band + size.Height)
        {return EnumMousePointPosition.MouseSizeBottom;}
        else
        {return EnumMousePointPosition.MouseDrag;}
       }
      }
     }
    }
    else
    {return EnumMousePointPosition.MouseSizeNone;}
   }
     
6、定义自己的MyMouseMove事件，在这个事件里，会使用上面设计的函数
   private void MyMouseMove(object sender,System.Windows.Forms.MouseEventArgs e)
   {
    Control lCtrl =(sender as Control);

    if (e.Button==MouseButtons.Left)
    {
     switch (m_MousePointPosition)
     {
      case EnumMousePointPosition.MouseDrag:      
       lCtrl.Left =lCtrl.Left+ e.X - p.X;
       lCtrl.Top =lCtrl.Top+ e.Y - p.Y;
       break;
      case EnumMousePointPosition.MouseSizeBottom:
       lCtrl.Height = lCtrl.Height + e.Y - p1.Y;
       p1.X=e.X;
       p1.Y=e.Y; //'记录光标拖动的当前点
       break;
      case EnumMousePointPosition.MouseSizeBottomRight:
       lCtrl.Width   = lCtrl.Width + e.X - p1.X;
       lCtrl.Height = lCtrl.Height + e.Y - p1.Y;
       p1.X=e.X;
       p1.Y=e.Y; //'记录光标拖动的当前点
       break;
      case EnumMousePointPosition.MouseSizeRight:
       lCtrl.Width   = lCtrl.Width + e.X - p1.X;      
//       lCtrl.Height = lCtrl.Height + e.Y - p1.Y;
       p1.X=e.X;
       p1.Y=e.Y; //'记录光标拖动的当前点
       break;
      case EnumMousePointPosition.MouseSizeTop:
       lCtrl.Top   = lCtrl.Top + (e.Y - p.Y);
       lCtrl.Height = lCtrl.Height - (e.Y - p.Y);
       break;
      case EnumMousePointPosition.MouseSizeLeft:
       lCtrl.Left   = lCtrl.Left + e.X - p.X;
       lCtrl.Width   = lCtrl.Width - (e.X - p.X);
       break;
      case EnumMousePointPosition.MouseSizeBottomLeft:
       lCtrl.Left   = lCtrl.Left + e.X - p.X;
       lCtrl.Width   = lCtrl.Width - (e.X - p.X);
       lCtrl.Height = lCtrl.Height+ e.Y - p1.Y;
       p1.X=e.X;
       p1.Y=e.Y; //'记录光标拖动的当前点
       break;
      case EnumMousePointPosition.MouseSizeTopRight:
       lCtrl.Top   = lCtrl.Top + (e.Y - p.Y);
       lCtrl.Width   = lCtrl.Width + (e.X - p1.X);
       lCtrl.Height = lCtrl.Height - (e.Y - p.Y);
       p1.X=e.X;
       p1.Y=e.Y; //'记录光标拖动的当前点
       break;
      case EnumMousePointPosition.MouseSizeTopLeft:
       lCtrl.Left   = lCtrl.Left + e.X - p.X;
       lCtrl.Top   = lCtrl.Top + (e.Y - p.Y);
       lCtrl.Width   = lCtrl.Width - (e.X - p.X);
       lCtrl.Height = lCtrl.Height - (e.Y - p.Y);
       break;
      default:
       break;
     }
     if (lCtrl.Width<MinWidth) lCtrl.Width=MinWidth;
     if (lCtrl.Height<MinHeight) lCtrl.Height=MinHeight;      

    }
    else
    {
     m_MousePointPosition = MousePointPosition(lCtrl.Size, e);   //'判断光标的位置状态
     switch (m_MousePointPosition)   //'改变光标
     {
      case EnumMousePointPosition.MouseSizeNone:
       this.Cursor = Cursors.Arrow;        //'箭头
       break;
      case EnumMousePointPosition.MouseDrag:
       this.Cursor = Cursors.SizeAll;      //'四方向
       break;
      case EnumMousePointPosition.MouseSizeBottom:
       this.Cursor = Cursors.SizeNS;       //'南北
       break;
      case EnumMousePointPosition.MouseSizeTop:
       this.Cursor = Cursors.SizeNS;       //'南北
       break;
      case EnumMousePointPosition.MouseSizeLeft:
       this.Cursor = Cursors.SizeWE;       //'东西
       break;
      case EnumMousePointPosition.MouseSizeRight:
       this.Cursor = Cursors.SizeWE;       //'东西
       break;
      case EnumMousePointPosition.MouseSizeBottomLeft:
       this.Cursor = Cursors.SizeNESW;     //'东北到南西
       break;
      case EnumMousePointPosition.MouseSizeBottomRight:
       this.Cursor = Cursors.SizeNWSE;     //'东南到西北
       break;
      case EnumMousePointPosition.MouseSizeTopLeft:
       this.Cursor = Cursors.SizeNWSE;     //'东南到西北
       break;
      case EnumMousePointPosition.MouseSizeTopRight:
       this.Cursor = Cursors.SizeNESW;     //'东北到南西
       break;
      default:
       break;
     }
    }

   }
  
7、制作一个初始化过程，将界面panel1上的所有控件都绑定MyMouseDown、MyMouseLeave、MyMouseMove事件，记得在Form初始化或者Form_Load时先执行它。

   private void initProperty()
   {
    for(int i = 0; i < this.panel1.Controls.Count; i++)
    {
     this.panel1.Controls[i].MouseDown+= new System.Windows.Forms.MouseEventHandler(MyMouseDown);
     this.panel1.Controls[i].MouseLeave+= new System.EventHandler(MyMouseLeave);
     this.panel1.Controls[i].MouseMove += new System.Windows.Forms.MouseEventHandler(MyMouseMove);
    }

   }
8、ok，在运行之前你在panel1上放几个控件，执行程序，应该可以随便移动、改变其大小了