Drag拖放数据操作示例

(一).功能描述

   涉及到DragEnter DragDrop DragLeave DragOver QueryContinueDrag事件用法的一个例子

(二).图片示例

演示将按钮Button1.Text文本"Button"拖动到TextBox中

拖动前:

拖动后:

(三).代码

using System;using System.Drawing;using System.Collections;using System.ComponentModel;using System.Windows.Forms;using System.Data;

namespace 拖放数据操作_按键事件_{ /// <summary> /// Form1 的摘要说明。 /// </summary> public class Form1 : System.Windows.Forms.Form {  private System.Windows.Forms.Button button1;  private System.Windows.Forms.TextBox textBox1;  /// <summary>  /// 必需的设计器变量。  /// </summary>  private System.ComponentModel.Container components = null;

  public Form1()  {   //   // Windows 窗体设计器支持所必需的   //   InitializeComponent();

   //   // TODO: 在 InitializeComponent 调用后添加任何构造函数代码   //  }

  /// <summary>  /// 清理所有正在使用的资源。  /// </summary>  protected override void Dispose( bool disposing )  {   if( disposing )   {    if (components != null)     {     components.Dispose();    }   }   base.Dispose( disposing );  }

  #region Windows 窗体设计器生成的代码  /// <summary>  /// 设计器支持所需的方法 - 不要使用代码编辑器修改  /// 此方法的内容。  /// </summary>  private void InitializeComponent()  {   this.button1 = new System.Windows.Forms.Button();   this.textBox1 = new System.Windows.Forms.TextBox();   this.SuspendLayout();   //    // button1   //    this.button1.Location = new System.Drawing.Point(112, 72);   this.button1.Name = "button1";   this.button1.TabIndex = 0;   this.button1.Text = "button1";   this.button1.QueryContinueDrag += new System.Windows.Forms.QueryContinueDragEventHandler(this.button1_QueryContinueDrag);   this.button1.MouseDown += new System.Windows.Forms.MouseEventHandler(this.button1_MouseDown);   //    // textBox1   //    this.textBox1.AccessibleDescription = "aaaaa";   this.textBox1.AccessibleName = "bbbbbb";   this.textBox1.AllowDrop = true;   this.textBox1.Location = new System.Drawing.Point(64, 160);   this.textBox1.Multiline = true;   this.textBox1.Name = "textBox1";   this.textBox1.Size = new System.Drawing.Size(168, 48);   this.textBox1.TabIndex = 1;   this.textBox1.Text = "";   this.textBox1.DragOver += new System.Windows.Forms.DragEventHandler(this.textBox1_DragOver);   this.textBox1.DragDrop += new System.Windows.Forms.DragEventHandler(this.textBox1_DragDrop);   this.textBox1.DragEnter += new System.Windows.Forms.DragEventHandler(this.textBox1_DragEnter);   this.textBox1.DragLeave += new System.EventHandler(this.textBox1_DragLeave);   //    // Form1   //    this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);   this.ClientSize = new System.Drawing.Size(292, 266);   this.Controls.Add(this.textBox1);   this.Controls.Add(this.button1);   this.Name = "Form1";   this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;   this.Text = "Form1";   this.ResumeLayout(false);

  }  #endregion

  /// <summary>  /// 应用程序的主入口点。  /// </summary>  [STAThread]  static void Main()   {   Application.Run(new Form1());  }

  private void button1_QueryContinueDrag(object sender, System.Windows.Forms.QueryContinueDragEventArgs e)  {   if(e.EscapePressed)    e.Action=DragAction.Cancel;  }

  private void button1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)  {   button1.DoDragDrop(button1.Text,DragDropEffects.Copy|DragDropEffects.Move);  }

  private void textBox1_DragEnter(object sender, System.Windows.Forms.DragEventArgs e)  {   if(e.Data.GetDataPresent(DataFormats.Text))    e.Effect=DragDropEffects.Copy;   else    e.Effect=DragDropEffects.None;  }

  private void textBox1_DragDrop(object sender, System.Windows.Forms.DragEventArgs e)  {   //使用KeyState属性   if((e.KeyState&(1<<3))!=0)   {    if((e.AllowedEffect&DragDropEffects.Copy)!=0)    {     e.Effect=DragDropEffects.Copy;     textBox1.Text=e.Data.GetData(DataFormats.Text).ToString();    }   }   else   {    e.Effect=DragDropEffects.Move;    textBox1.Text=e.Data.GetData(DataFormats.Text).ToString();   }  }

  private void textBox1_DragLeave(object sender, System.EventArgs e)  {   textBox1.Text="执行 DragLeave";  }

  private void textBox1_DragOver(object sender, System.Windows.Forms.DragEventArgs e)  {   textBox1.Text="执行 DragOver";  } }} (四). 示例下载

      http://www.cnblogs.com/Files/ChengKing/拖放数据操作(按键事件).rar