ListBox的应用

<div>
   
        <asp:ListBox ID="ListBox1" runat="server" Height="319px"
            SelectionMode="Multiple" Width="187px">
            <asp:ListItem>001</asp:ListItem>
            <asp:ListItem>002</asp:ListItem>
            <asp:ListItem>003</asp:ListItem>
            <asp:ListItem>004</asp:ListItem>
            <asp:ListItem>005</asp:ListItem>
            <asp:ListItem>006</asp:ListItem>
        </asp:ListBox>
        <asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="添加" />
        <asp:Button ID="Button2" runat="server" Text="免除" onclick="Button2_Click" />
        <asp:ListBox ID="ListBox2" runat="server" Height="323px"
            SelectionMode="Multiple" Width="192px"></asp:ListBox>
   
    </div>

 

后台

 List<ListItem> list = new List<ListItem>();
        protected void Button1_Click(object sender, EventArgs e)// 增加
        {
            for (int i = ListBox1.Items.Count-1; i >= 0; i--)
            {
                if(ListBox1.Items[i].Selected==true)
                {
                 list.Add(ListBox1.Items[i]);
                 ListBox1.Items.Remove(ListBox1.Items[i]);
                }
            }
            for (int i = list.Count-1; i >=0; i--)
            {
                ListBox2.Items.Add(list[i]);
            }
        }

        protected void Button2_Click(object sender, EventArgs e)//移除;‘’
        {
            for (int i = ListBox2.Items.Count - 1; i >= 0; i--)
            {
                if (ListBox2.Items[i].Selected == true)
                {
                    list.Add(ListBox2.Items[i]);
                    ListBox2.Items.Remove(ListBox2.Items[i]);
                }
            }
            for (int i = list.Count - 1; i >= 0;i-- )
            {
                ListBox1.Items.Add(list[i]);
            }
           
        }