winform 控件拖动和改变大小的例子
要实现界面上控件的可调整大小和位置可以用下面的代码实现，主要是对Panel控件进行了一点改造，应该也适用于其他容器控件。
欢迎大家到我的网站去下载实例。如果有什么不对的地方，请大家指正。
主要的思路是在容器内为所有的控件添加MouseDown,MouseLeave,MouseMove三个事件，在MouseLeave事件中保存对控件位置和大小的修改，保存到XML文件中，程序启动时会调用XML文件内的控件属性，以此来实现该功能。
下面是Panel类代码。
public partial class PanelEx :Panel
{
/// <summary>
/// 光标状态
/// </summary>
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
}
#region 属性
private static string xmlDocPath = "";
private XmlDocument doc;
private const int Band = 5;
private const int MinWidth = 10;
private const int MinHeight = 10;
private EnumMousePointPosition m_MousePointPosition;
private Point p, p1;
#endregion
public PanelEx()
{
InitializeComponent();
}
#region 改变控件大小和移动位置用到的方法
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;
}
/// <summary>
/// 鼠标离开事件需要改进
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void MyMouseLeave(object sender, EventArgs e)
{
Control s = (Control)sender;
SaveStyle(s);
m_MousePointPosition = EnumMousePointPosition.MouseSizeNone;
this.Cursor = Cursors.Arrow;
}
private void SaveStyle(Control s)
{
XmlNodeList nodes = doc.GetElementsByTagName(s.Name);
XmlElement xn;
if (nodes.Count != 1)
{
xn = doc.CreateElement(s.Name);
}
else
{
xn = (XmlElement)doc.GetElementsByTagName(s.Name)[0];
}
if (s.Top < 0 || s.Top > this.Height - s.Top)
s.Top = 0;
xn.SetAttribute("Top", s.Top.ToString());
if (s.Left < 0 || s.Left > this.Width - s.Left)
s.Left = 0;
xn.SetAttribute("Left", s.Left.ToString());
if (s.Width + s.Left > this.Width)
s.Width = this.Width - s.Left;
xn.SetAttribute("Width", s.Width.ToString());
if (s.Height + s.Top > this.Height)
s.Height = this.Height - s.Top;
xn.SetAttribute("Height", s.Height.ToString());
XmlNodeList xnl = doc.GetElementsByTagName(this.Name);
XmlElement xnp;
if (xnl.Count < 1)
{
xnp = doc.CreateElement(this.Name);
}
else
{
xnp = (XmlElement)xnl[0];
}
xnp.AppendChild((XmlNode)xn);
doc.DocumentElement.AppendChild((XmlNode)xnp);
doc.Save(xmlDocPath);
}
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; }
}
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;
}
}
}
#endregion
#region 初始化鼠标事件委托和控件大小和移动
private void initProperty()
{
for (int i = 0; i < this.Controls.Count; i++)
{
this.Controls[i].MouseDown += new System.Windows.Forms.MouseEventHandler(MyMouseDown);
this.Controls[i].MouseLeave += new System.EventHandler(MyMouseLeave);
this.Controls[i].MouseMove += new System.Windows.Forms.MouseEventHandler(MyMouseMove);
}
}
private void initStyle()
{
Control s;
for (int i = 0; i < this.Controls.Count; i++)
{
s = this.Controls[i];
XmlNodeList nodes = doc.GetElementsByTagName(s.Name);
if (nodes.Count == 1)
{
XmlAttributeCollection xac = nodes[0].Attributes;
foreach (XmlAttribute xa in xac)
{
if (xa.Value == "")
continue;
switch (xa.Name)
{
case "Top":
var Top = Convert.ToInt32(xa.Value);
s.Top = Top;
break;
case "Left":
var Left = Convert.ToInt32(xa.Value);
s.Left = Left;
break;
case "Width":
var Width = Convert.ToInt32(xa.Value);
s.Width = Width;
break;
case "Height":
var Height = Convert.ToInt32(xa.Value);
s.Height = Height;
break;
default:
break;
}
}
}
}
}
#endregion
/// <summary>
/// 用于实现容器内控件移动和改变大小的方法
/// </summary>
/// <param name="XmlDoc">用于保存控件的属性的XML文档</param>
public void InitMouseAndContolStyle(string XmlDocPath)
{
xmlDocPath = XmlDocPath;
doc = new XmlDocument();
doc.Load(XmlDocPath);
initProperty();
initStyle();
}
}
