在上面的MouseMove中多了一个方法--ControlMove，这个就是根据不同的枚举值，计算控件的移动方式和大小的方法。该方法中同时对控件的最小宽度和高度做了处理。添加如下两个字段。
private int MinWidth = 20; //最小宽度
private int MinHeight = 20;//最小高度
/// <summary>
/// 控件移动
/// </summary>
private void ControlMove()
{
cPoint = Cursor.Position;
int x = cPoint.X - pPoint.X;
int y = cPoint.Y - pPoint.Y;
switch (this.mpoc)
{
case MousePosOnCtrl.TOP:
if (baseControl.Height - y > MinHeight)
{
baseControl.Top += y;
baseControl.Height -= y;
}
else
{
baseControl.Top -= MinHeight - baseControl.Height;
baseControl.Height = MinHeight;
}
break;
case MousePosOnCtrl.BOTTOM:
if (baseControl.Height + y > MinHeight)
{
baseControl.Height += y;
}
else
{
baseControl.Height = MinHeight;
}
break;
case MousePosOnCtrl.LEFT:
if (baseControl.Width - x > MinWidth)
{
baseControl.Left += x;
baseControl.Width -= x;
}
else
{
baseControl.Left -= MinWidth - baseControl.Width;
baseControl.Width = MinWidth;
}
break;
case MousePosOnCtrl.RIGHT:
if (baseControl.Width + x > MinWidth)
{
baseControl.Width += x;
}
else
{
baseControl.Width = MinWidth;
}
break;
case MousePosOnCtrl.TOPLEFT:
if (baseControl.Height - y > MinHeight)
{
baseControl.Top += y;
baseControl.Height -= y;
}
else
{
baseControl.Top -= MinHeight - baseControl.Height;
baseControl.Height = MinHeight;
}
if (baseControl.Width - x > MinWidth)
{
baseControl.Left += x;
baseControl.Width -= x;
}
else
{
baseControl.Left -= MinWidth - baseControl.Width;
baseControl.Width = MinWidth;
}
break;
case MousePosOnCtrl.TOPRIGHT:
if (baseControl.Height - y > MinHeight)
{
baseControl.Top += y;
baseControl.Height -= y;
}
else
{
baseControl.Top -= MinHeight - baseControl.Height;
baseControl.Height = MinHeight;
}
if (baseControl.Width + x > MinWidth)
{
baseControl.Width += x;
}
else
{
baseControl.Width = MinWidth;
}
break;
case MousePosOnCtrl.BOTTOMLEFT:
if (baseControl.Height + y > MinHeight)
{
baseControl.Height += y;
}
else
{
baseControl.Height = MinHeight;
}
if (baseControl.Width - x > MinWidth)
{
baseControl.Left += x;
baseControl.Width -= x;
}
else
{
baseControl.Left -= MinWidth - baseControl.Width;
baseControl.Width = MinWidth;
}
break;
case MousePosOnCtrl.BOTTOMRIGHT:
if (baseControl.Height + y > MinHeight)
{
baseControl.Height += y;
}
else
{
baseControl.Height = MinHeight;
}
if (baseControl.Width + x > MinWidth)
{
baseControl.Width += x;
}
else
{
baseControl.Width = MinWidth;
}
break;
}
pPoint = Cursor.Position;
}
