本文实例讲述了C# WinForm实现窗体上控件自由拖动功能。分享给大家供大家参考，具体如下：

说明：首先在窗体上放一个PictrueBox控件，命名为pb1,拖动完整代码如下：

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;namespace WinFormDrag{ public partial class Form1 : Form { //鼠标按下坐标（control控件的相对坐标） Point mouseDownPoint = Point.Empty; //显示拖动效果的矩形 Rectangle rect = Rectangle.Empty; //是否正在拖拽 bool isDrag = false; public Form1() { InitializeComponent(); } private void Form1_Paint(object sender, PaintEventArgs e) { if (rect != Rectangle.Empty) { if (isDrag) {//画一个和Control一样大小的黑框 e.Graphics.DrawRectangle(Pens.Black, rect); } else { e.Graphics.DrawRectangle(new Pen(this.BackColor), rect); } } } /// <summary> /// 按下鼠标时 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void pb1_MouseDown(object sender, MouseEventArgs e) { if (e.Button == MouseButtons.Left) { mouseDownPoint = e.Location; //记录控件的大小 rect = pb1.Bounds; } } /// <summary> /// 移过时 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void pb1_MouseMove(object sender, MouseEventArgs e) { if (e.Button == MouseButtons.Left) { isDrag = true; //重新设置rect的位置，跟随鼠标移动 rect.Location = getPointToForm(new Point(e.Location.X - mouseDownPoint.X, e.Location.Y - mouseDownPoint.Y)); this.Refresh(); } } /// <summary> /// 释放鼠标按钮时 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void pb1_MouseUp(object sender, MouseEventArgs e) { if (e.Button == MouseButtons.Left) { if (isDrag) { isDrag = false; //移动control到放开鼠标的地方 pb1.Location = rect.Location; this.Refresh(); } reset(); } } //重置变量 private void reset() { mouseDownPoint = Point.Empty; rect = Rectangle.Empty; isDrag = false; } //把相对与control控件的坐标，转换成相对于窗体的坐标。 private Point getPointToForm(Point p) { return this.PointToClient(pb1.PointToScreen(p)); } }}

更多关于C#相关内容感兴趣的读者可查看本站专题：《WinForm控件用法总结》、《C#窗体操作技巧汇总》、《C#数据结构与算法教程》、《C#常见控件用法教程》、《C#面向对象程序设计入门教程》及《C#程序设计之线程使用技巧总结》

希望本文所述对大家C#程序设计有所帮助。