private void select_comp_Load(object sender, EventArgs e)
        {
            CobGroup.Text = "请选择";
            GroupInfo();
        }
        private void GroupInfo()
        {
            DirectoryEntry MainGroup = new DirectoryEntry("WinNT:");
            CobGroup.Items.Add("请选择");
            foreach (DirectoryEntry domain in MainGroup.Children)
            {

                CobGroup.Items.Add(domain.Name.ToString());

            }
        }

        private void ComputerInfo(string strname)
        {

            DirectoryEntry MainGroup = new DirectoryEntry("WinNT:");
            foreach (DirectoryEntry domain in MainGroup.Children)
            {

                if (domain.Name == strname)
                {
                    foreach (DirectoryEntry pc in domain.Children)
                    {
                        if (pc.Name != "Schema")//Schema是结束标记   
                            CobComputer.Items.Add(pc.Name);

                    }
                }
            }

        }

        private void CobGroup_SelectedIndexChanged(object sender, EventArgs e)
        {
          ComputerInfo(CobGroup.Text);
        }

首先，确定你的CobGroup_SelectedIndexChanged方法是被调用到的。
其次，高个断点，跟踪一下看看。

你是不是想用CobGroup_SelectedIndexChanging方法啊，那样代码就放错位置了？！

我是想在更改下拉列表的值时执行ComputerInfo(CobGroup.Text);

那就应该是在CobGroup_SelectedIndexChanging事件中写代码啊,试试看

CobGroup_SelectedIndexChanging？？
有这个事件吗？？
 
LZ,你检查了没有？

只有SelectedIndexChange和SelectedValueChange事件，运行时就是没效果，晕

把你和这个代码相关的文件都发上来.

using System;
using System.Collections.Generic;
using
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.DirectoryServices;

namespace SMS
{
    public partial class select_comp : Form
    {
        public select_comp()
        {
            InitializeComponent();
        }

        public string COMPUTERS
        {
            get {
                return CobComputer.Text;
            }
        }

        private void select_comp_Load(object sender, EventArgs e)
        {
            CobGroup.Text = "请选择";
            GroupInfo();
        }
        private void GroupInfo()
        {
            DirectoryEntry MainGroup = new DirectoryEntry("WinNT:");
            CobGroup.Items.Add("请选择");
            foreach (DirectoryEntry domain in MainGroup.Children)
            {

                CobGroup.Items.Add(domain.Name.ToString());

            }
        }

        private void ComputerInfo(string strname)
        {

            DirectoryEntry MainGroup = new DirectoryEntry("WinNT:");
            foreach (DirectoryEntry domain in MainGroup.Children)
            {

                if (domain.Name == strname)
                {
                    foreach (DirectoryEntry pc in domain.Children)
                    {
                        if (pc.Name != "Schema")//Schema是结束标记   
                            CobComputer.Items.Add(pc.Name);

                    }
                }
            }

        }

        private void CobGroup_SelectedIndexChanged(object sender, EventArgs e)
        {
            CobComputer.Items.Clear();
            ComputerInfo(CobGroup.Text);
        }

        
        private void button2_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void CobGroup_Click(object sender, EventArgs e)
        {

            CobGroup_SelectedIndexChanged(sender, e);
        }
    }
}



我的目的是程序运行时自动加载网络所有工作组，选取某一工作组时显示所有该工作组的计算机




[ 本帖最后由 ycbbg 于 2010-9-21 11:26 编辑 ]

select_comp.Designer.cs文件代码放上来。