自己做了窗体控件,怎么实现鼠标拖动边框,大小就改变.

Question

准备自己做一个比较独特的窗体控件,到了用鼠标拖动边框时不能实现变大,只能变小.是不是要获得鼠标在屏幕中的坐标,怎么能实现呢.还请各位高手能指点

Answer 1

/// <summary>
/// 鼠标左击标题栏处理程序，开始移动本控件
/// 2004-10-04 修改，改为移动焦点框
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void TitlePanel_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
if(!this.Entered)
{
this.Focus();
Entered=true;
}
if( (e.Button==MouseButtons.Left) )
{ Moving=true;
OldLeft = e.X;
OldTop = e.Y;
//获取屏幕上下文 Common.ClipCursorIn(this.Parent);
ScreenDC = Crownwood.Magic.Win32.User32.GetDC(System.IntPtr.Zero);
Point p = new Point(0,0);
p = this.Parent.PointToScreen(p);
ClipRgn = WinAPI.CreateRectRgn(p.X,p.Y,p.X + this.Parent.Width,p.Y + this.Parent.Height);
WinAPI.SelectClipRgn(ScreenDC,ClipRgn);
//rect.left = -900;
#region 画焦点框
rect.left = this.Left;
rect.top = this.Top;
rect.right = this.Left + this.Width;
rect.bottom = this.Top + this.Height; p = new Point(rect.left,rect.top);
p = this.Parent.PointToScreen(p);
rect.left = p.X;
rect.top = p.Y;

p = new Point(rect.right,rect.bottom);
p = this.Parent.PointToScreen(p);
rect.right = p.X;
rect.bottom = p.Y;
Crownwood.Magic.Win32.User32.DrawFocusRect(ScreenDC,ref rect);
#endregion
//Crownwood.Magic.Win32.User32.
}
}
/// <summary>
/// 鼠标在标题栏移动时的程序，移动本控件
/// 2004-10-04 修改，改为移动焦点框
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void TitlePanel_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
{
if( Moving )
{

//将以前的重新画一遍 //if(rect.left != -900)
Crownwood.Magic.Win32.User32.DrawFocusRect(ScreenDC,ref rect);
rect.left = this.Left + e.X - OldLeft;
rect.top = this.Top + e.Y - OldTop;
rect.right = rect.left + this.Width;
rect.bottom = rect.top + this.Height; Point p = new Point(rect.left,rect.top);
p = this.Parent.PointToScreen(p);
rect.left = p.X;
rect.top = p.Y;

p = new Point(rect.right,rect.bottom);
p = this.Parent.PointToScreen(p);
rect.right = p.X;
rect.bottom = p.Y;
Crownwood.Magic.Win32.User32.DrawFocusRect(ScreenDC,ref rect);
}
}
/// <summary>
/// 鼠标键在标题栏释放处理程序，移动本控件结束
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void TitlePanel_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
{
if (Moving) 
{
Crownwood.Magic.Win32.User32.DrawFocusRect(ScreenDC,ref rect);
if ((this.Left!=this.Left+e.X+OldLeft)
||(this.Top!=this.Top+e.Y-OldTop))
{
this.Left=this.Left+e.X  - OldLeft;
this.Top=this.Top+e.Y  - OldTop;
}

Common.RestoreCursor();
WinAPI.DeleteObject(ClipRgn);
Crownwood.Magic.Win32.User32.ReleaseDC(System.IntPtr.Zero,ScreenDC);
this.Parent.Refresh();
}
Moving=false;
if(e.Button==MouseButtons.Right&&PopMenu!=null)
PopMenu.TrackPopup(TitlePanel.PointToScreen(new Point(e.X,e.Y)));
//if Assigned(FOnColRePaint) then
//    FOnColRePaint(self);
}

Answer 2

谢谢xxj!但有很多地方不明白.能不能再给我讲讲Common.ClipCursorIn(this.Parent);
ScreenDC = Crownwood.Magic.Win32.User32.GetDC(System.IntPtr.Zero);

Answer 3

[DllImport("User32.dll")]
public static System.IntPtr GetDC ( System.IntPtr hWnd );ClipCursorIn(this.Parent);/// <summary>
/// 锁定鼠标光标活动范围，引入自user32.dll
/// </summary>
/// <param name="r"></param>
[DllImport("user32.dll")]
public extern static void ClipCursor(RECT r);