1 using System;  2 using System.Collections.Generic;  3 using System.Linq;  4 using System.Web;  5 using System.Web.UI;  6 using System.Web.UI.WebControls;  7 using System.Data;  8 using System.Data.SqlClient;  9 using System.Configuration; 10  11 public partial class MyListBox : System.Web.UI.Page 12 { 13     protected void Page_Load(object sender, EventArgs e) 14     { 15         if (!IsPostBack) 16         { 17             //让按钮事件和AddAndDelete_Command方法建立关联 18             this.btnAddOne.Command += new CommandEventHandler(this.AddAndDelete_Command); 19             this.btnAddAll.Command += new CommandEventHandler(this.AddAndDelete_Command); 20             this.btnDeleteOne.Command += new CommandEventHandler(this.AddAndDelete_Command); 21             this.btnDeleteAll.Command += new CommandEventHandler(this.AddAndDelete_Command); 22  23             //另一种建立关联的写法 24             //this.btnAddOne.Click += new EventHandler(this.AddAndDelete_Command); 25             //this.btnAddAll.Click += new EventHandler(this.AddAndDelete_Command); 26             //this.btnDeleteOne.Click += new EventHandler(this.AddAndDelete_Command); 27             //this.btnDeleteAll.Click += new EventHandler(this.AddAndDelete_Command); 28  29             //加载并显示数据 30             GetUserName(); 31         } 32     } 33  34     //加载数据,绑定到SourceList控件 35     private void GetUserName() 36     { 37         //清空ListBox控件的所有数据项 38         SourceList.Items.Clear(); 39  40         //连接、读取数据，并把数据绑定到SourceList控件 41         string con = ConfigurationManager.ConnectionStrings["SqlConn"].ConnectionString; 42         SqlConnection myCon = new SqlConnection(con); 43         string cmdText = "SELECT UI_UserID,UI_UserName FROM tb_UserInfo ORDER BY UI_UserID"; 44         SqlCommand myCom = new SqlCommand(cmdText, myCon); 45  46         myCon.Open(); 47         SqlDataReader myReader = myCom.ExecuteReader(); 48  49         while (myReader.Read()) 50         { 51             SourceList.Items.Add(new ListItem(myReader["UI_UserName"].ToString(), myReader["UI_UserID"].ToString())); 52         } 53  54         myReader.Close(); 55         myCon.Close(); 56     } 57  58     //根据按钮控件的CommandName属性进行判断而进行不同的操作 59     public void AddAndDelete_Command(object sender, System.EventArgs e) 60     { 61         string commandName = ((Button)sender).CommandName; 62  63         switch (commandName) 64         { 65             case "addOne": 66                 if (SourceList.SelectedIndex > -1) 67                 { 68                     DirectList.Items.Add(SourceList.SelectedItem); 69                     lblSucessMessage.Visible = false; 70                 } 71                 else 72                 { 73                     lblSucessMessage.Visible = true; 74                 } 75                 break; 76             case "addAll": 77                 lblSucessMessage.Visible = false; 78                 DirectList.Items.Clear(); 79                 foreach (ListItem item in SourceList.Items) 80                 { 81                     DirectList.Items.Add(item); 82                 } 83                 break; 84             case "deleteOne": 85                 if (DirectList.SelectedIndex > -1) 86                 { 87                     DirectList.Items.Remove(DirectList.SelectedItem); 88                     lblSucessMessage.Visible = false; 89                 } 90                 else 91                 { 92                     lblSucessMessage.Visible = true; 93                 } 94                 break; 95             case "deleteAll": 96                 lblSucessMessage.Visible = false; 97                 DirectList.Items.Clear(); 98                 break; 99             default: break;100         }101 102         //清空两个列表控件的选项103         SourceList.SelectedIndex = -1;104         DirectList.SelectedIndex = -1;105     }106 }