关于Button控件的CommandName属性用法的一个实例 - 悠閒

关于Button控件的CommandName属性用法的一个实例

前台截图：

例子中有两个ListBox控件、四个Button控件和一个Label控件。数据显示需要绑定数据库。

例子要实现的功能很简单：利用Button控件的CommandName属性来操作两个ListBox控件中数据的移动。

前台代码：

MyListBox.aspx

后台代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;

public partial class MyListBox : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            //让按钮事件和AddAndDelete_Command方法建立关联
            this.btnAddOne.Command += new CommandEventHandler(this.AddAndDelete_Command);
            this.btnAddAll.Command += new CommandEventHandler(this.AddAndDelete_Command);
            this.btnDeleteOne.Command += new CommandEventHandler(this.AddAndDelete_Command);
            this.btnDeleteAll.Command += new CommandEventHandler(this.AddAndDelete_Command);

            //另一种建立关联的写法
            //this.btnAddOne.Click += new EventHandler(this.AddAndDelete_Command);
            //this.btnAddAll.Click += new EventHandler(this.AddAndDelete_Command);
            //this.btnDeleteOne.Click += new EventHandler(this.AddAndDelete_Command);
            //this.btnDeleteAll.Click += new EventHandler(this.AddAndDelete_Command);

            //加载并显示数据
            GetUserName();
        }
    }

    //加载数据,绑定到SourceList控件
    private void GetUserName()
    {
        //清空ListBox控件的所有数据项
        SourceList.Items.Clear();

        //连接、读取数据，并把数据绑定到SourceList控件
        string con = ConfigurationManager.ConnectionStrings["SqlConn"].ConnectionString;
        SqlConnection myCon = new SqlConnection(con);
        string cmdText = "SELECT UI_UserID,UI_UserName FROM tb_UserInfo ORDER BY UI_UserID";
        SqlCommand myCom = new SqlCommand(cmdText, myCon);

        myCon.Open();
        SqlDataReader myReader = myCom.ExecuteReader();

        while (myReader.Read())
        {
            SourceList.Items.Add(new ListItem(myReader["UI_UserName"].ToString(), myReader["UI_UserID"].ToString()));
        }

        myReader.Close();
        myCon.Close();
    }

    //根据按钮控件的CommandName属性进行判断而进行不同的操作
    public void AddAndDelete_Command(object sender, System.EventArgs e)
    {
        string commandName = ((Button)sender).CommandName;

        switch (commandName)
        {
            case "addOne":
                if (SourceList.SelectedIndex > -1)
                {
                    DirectList.Items.Add(SourceList.SelectedItem);
                    lblSucessMessage.Visible = false;
                }
                else
                {
                    lblSucessMessage.Visible = true;
                }
                break;
            case "addAll":
                lblSucessMessage.Visible = false;
                DirectList.Items.Clear();
                foreach (ListItem item in SourceList.Items)
                {
                    DirectList.Items.Add(item);
                }
                break;
            case "deleteOne":
                if (DirectList.SelectedIndex > -1)
                {
                    DirectList.Items.Remove(DirectList.SelectedItem);
                    lblSucessMessage.Visible = false;
                }
                else
                {
                    lblSucessMessage.Visible = true;
                }
                break;
            case "deleteAll":
                lblSucessMessage.Visible = false;
                DirectList.Items.Clear();
                break;
            default: break;
        }

        //清空两个列表控件的选项
        SourceList.SelectedIndex = -1;
        DirectList.SelectedIndex = -1;
    }
}

posted on 2009-11-24 09:51 悠閒阅读(12053) 评论(0) 编辑收藏举报

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