效果预览：
实现步骤如下：
（1）首先在项目上右击选择：添加->新建项，添加自定义控件
（2）自定义的一个Label让它继承LabelControl控件，LabelControl控件是DevExpress控件库里面的一种，和Label控件差不多，想了解更多关于DevExpress控件，推荐到DevExpress控件论坛学习：
public partial class LabelModule : LabelControl
（3）这个Label需要实现的MouseDown。
private void LabelModule_MouseDown(object sender, MouseEventArgs e)
{
IsMouseDown = true;
MousePrePosition = new Point(e.X, e.Y);
this.BorderStyle = DevExpress.XtraEditors.Controls.BorderStyles.Simple;
this.Cursor = Cursors.SizeAll;
}
（4）MouseUp，也就是鼠标弹起的方法。
private void LabelModule_MouseUp(object sender, MouseEventArgs e)
{
IsMouseDown = false;
this.BorderStyle = DevExpress.XtraEditors.Controls.BorderStyles.Default;
this.Cursor = Cursors.Default;
}
（5）MouseMove，也就是鼠标移动时的方法。
private void LabelModule_MouseMove(object sender, MouseEventArgs e)
{
if (!IsMouseDown) return;
this.Top = this.Top + (e.Y - MousePrePosition.Y);
this.Left = this.Left + (e.X - MousePrePosition.X);
}
e.X,e.Y 指的是：鼠标的坐标因所引发的事件而异。例如，当处理 Control.MouseMove 事件时，鼠标的坐标值是相对于引发事件的控件的坐标。一些与拖放操作相关的事件具有相对于窗体原点或屏幕原点的关联的鼠标坐标值。
完整代码：LabelModule.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using DevExpress.XtraEditors;
namespace IJPrinterSoftware
{
public partial class LabelModule : LabelControl
{
private bool IsMouseDown = false;
private Point MousePrePosition;
private void init()
{
InitializeComponent();
this.MouseDown += new MouseEventHandler(LabelModule_MouseDown);
this.MouseUp += new MouseEventHandler(LabelModule_MouseUp);
this.MouseMove+=new MouseEventHandler(LabelModule_MouseMove);
}
public LabelModule()
{
init();
}
private void LabelModule_MouseDown(object sender, MouseEventArgs e)
{
IsMouseDown = true;
MousePrePosition = new Point(e.X, e.Y);
this.BorderStyle = DevExpress.XtraEditors.Controls.BorderStyles.Simple;
this.Cursor = Cursors.SizeAll;
}
private void LabelModule_MouseUp(object sender, MouseEventArgs e)
{
IsMouseDown = false;
this.BorderStyle = DevExpress.XtraEditors.Controls.BorderStyles.Default;
this.Cursor = Cursors.Default;
}
private void LabelModule_MouseMove(object sender, MouseEventArgs e)
{
if (!IsMouseDown) return;
this.Top = this.Top + (e.Y - MousePrePosition.Y);
this.Left = this.Left + (e.X - MousePrePosition.X);
}
}
}
