错哪了？在线！！！！

Line 18: ListItem item=lbox2.Items[i];

参考void Check_Clicked(Object sender, EventArgs e) {
          Message.Text="Selected Item(s):" + "<br>" + "<br>";
          for (int i=0; i<checkboxlist1.Items.Count; i++) {
             if (checkboxlist1.Items[i].Selected)
                Message.Text=Message.Text + checkboxlist1.Items[i].Text + "<br>";
          }
       }

for(int i=0; i<lbox2.Items.Count;i++)
       ListItem item=lbox2.Items[i];
      if(item.Selected)
   {
            lbox1.Items.Add(item);
    lbox2.Items.Remove(item);
    }
==============>
for (int i=0; i<lbox2.Items.Count; i++) {
   if (lbox2.Items[i].Selected)
     lbox1.Items.Add(lbox2.Items[i].Text);
     lbox2.Items.Remove(lbox2.Items[i].Text);
}兄弟，你也太懒了点吧

我改后的代码，运行是空白！怪！！！！！
<% @ Page language="C#"%>
<script language="C#" runat="server">
public void ToRightList(object sender,EventArgs e)
{
      for (int i=0; i<lbox1.Items.Count; i++) {
      if (lbox1.Items[i].Selected)
        lbox2.Items.Add(lbox1.Items[i].Text);
        lbox1.Items.Remove(lbox1.Items[i].Text);
} }
public void ToLeftList(object sender,EventArgs e)
    {
  for (int i=0; i<lbox2.Items.Count; i++) {
           if (lbox2.Items[i].Selected)
           lbox1.Items.Add(lbox2.Items[i].Text);
           lbox2.Items.Remove(lbox2.Items[i].Text);
        }       }
      </script>
      <html>
      <head>
      <title><title>
      </head>
      <body>
      <b>ListBox演示</b>
      <hr>
      <form runat="server">
      <table>
      <tr>
      <td>
           <b>ListBox容器1：</b><br>
      <asp:ListBox id="lbox1" Rows=5 SelectionMode="Multiple" runat="server">
        <asp:ListItem>天天</asp:ListItem>
    <asp:ListItem>天健</asp:ListItem>
    <asp:ListItem>皇帝</asp:ListItem>
    <asp:ListItem>皇后</asp:ListItem>
    <asp:ListItem>靖靖</asp:ListItem>
                </asp:ListBox>
            </td>
    <td>
     <asp:Button id="ToRight" Text="-->" OnClick="ToRightList" runat="server"/></br>
     <asp:Button id="ToLeft" Text="<--" OnClick="ToLeftList" runat="server"/>
     </td>
     <td>
     <b>ListBox容器2：</b><br>
     <asp:ListBox id="lbox2" Rows=5 SelectionMode="Multiple" runat="server"/>
     </td>
     </form>
     </body>
     </html>

你下面的/table没有，上面的/title写错了private void ToRight_Click(object sender, System.EventArgs e)
{
for(int i=0; i<lbox1.Items.Count;i++)
{
ListItem item=lbox1.Items[i];
if(item.Selected)
{
lbox2.Items.Add(item.Text);
lbox1.Items.Remove(item);
}
}
} private void ToLeft_Click(object sender, System.EventArgs e)
{
for(int i=0; i<lbox2.Items.Count;i++)
{
ListItem item=lbox2.Items[i];
if(item.Selected)
{
lbox1.Items.Add(item.Text);
lbox2.Items.Remove(item);
}
}
}

前台：
<%@ Page language="c#" Codebehind="WebForm1.aspx.cs" AutoEventWireup="false" Inherits="WebApplication2.WebForm1" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
<HEAD>
<title></title>
</HEAD>
<body>
<b>ListBox演示</b>
<hr>
<form runat="server" ID="Form1">
<table>
<tr>
<td>
<b>ListBox容器1：</b><br>
<asp:ListBox id="lbox1" Rows="5" SelectionMode="Multiple" runat="server">
<asp:ListItem>天天</asp:ListItem>
<asp:ListItem>天健</asp:ListItem>
<asp:ListItem>皇帝</asp:ListItem>
<asp:ListItem>皇后</asp:ListItem>
<asp:ListItem>靖靖</asp:ListItem>
</asp:ListBox>
</td>
<td>
<asp:Button id="ToRight" Text="-->" runat="server" /><BR>
<asp:Button id="ToLeft" Text="<--" runat="server" />
</td>
<td>
<b>ListBox容器2：</b><br>
<asp:ListBox id="lbox2" Rows="5" SelectionMode="Multiple" runat="server" />
</td>
</tr>
</table>
</form>
</body>
</HTML>

后台：
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;namespace WebApplication2
{
/// <summary>
/// Summary description for WebForm1.
/// </summary>
public class WebForm1 : System.Web.UI.Page
{
protected System.Web.UI.WebControls.ListBox lbox1;
protected System.Web.UI.WebControls.Button ToRight;
protected System.Web.UI.WebControls.Button ToLeft;
protected System.Web.UI.WebControls.ListBox lbox2;

private void Page_Load(object sender, System.EventArgs e)
{
// Put user code to initialize the page here
} #region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}

/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.ToRight.Click += new System.EventHandler(this.ToRight_Click);
this.ToLeft.Click += new System.EventHandler(this.ToLeft_Click);
this.Load += new System.EventHandler(this.Page_Load); }
#endregion private void ToRight_Click(object sender, System.EventArgs e)
{
for(int i=0; i<lbox1.Items.Count;i++)
{
ListItem item=lbox1.Items[i];
if(item.Selected)
{
lbox2.Items.Add(item.Text);
lbox1.Items.Remove(item);
}
}
} private void ToLeft_Click(object sender, System.EventArgs e)
{
for(int i=0; i<lbox2.Items.Count;i++)
{
ListItem item=lbox2.Items[i];
if(item.Selected)
{
lbox1.Items.Add(item.Text);
lbox2.Items.Remove(item);
}
}
}
}
}

哪位仁兄，解释下前台后台，不懂！
我一直就一下就运行出来！
回复人： wangsaokui(无间道II(前传)) 分一定给！就今12点前吧！

晚了，兄弟！前台就是你的页面，文件名后缀为aspx
后台就是你的代码，文件名后缀为aspx.vb或aspx.cs

调试易

错哪了？在线！！！！

解决方案 »