ListBox控件使用
ListBox 可以通过ListSelectionMode 设置多选,默认值为 Single,
<%@ Page Language="C#" AutoEventWireup="True" %>
<html>
<head>
<script runat="server">
void AddBtn_Click(Object Sender, EventArgs e)
{
if (ListBox1.SelectedIndex > -1) //检查是否有选中项,否则会报错!未将引用指向对象实列
{
if (ListBox2.Items.FindByValue(ListBox1.SelectedItem.Text) == null) //如果2中未存在选中的值
{
ListItem Item = new ListItem();
// Text and Value are swapped.
Item.Text = ListBox1.SelectedItem.Value;
Item.Value = ListBox1.SelectedItem.Text;
ListBox2.Items.Add(Item);
}
}
}
void DelBtn_Click(Object Sender, EventArgs e)
{
if (ListBox2.SelectedIndex > -1) //检查是否有选中项,否则会报错!未将引用指向对象实列
{
ListBox2.Items.Remove(ListBox2.SelectedItem);
}
}
</script>
</head>
<body>
<h3>ListItem Example</h3>
<p>
<form runat=server>
<table>
<tr><td>
<asp:ListBox id=ListBox1 Width="100px" runat="server">
<asp:ListItem Value="Value 1">Item 1</asp:ListItem>//一种添加方式
<asp:ListItem Value="Value 2">Item 2</asp:ListItem>
<asp:ListItem Value="Value 3">Item 3</asp:ListItem>
<asp:ListItem Value="Value 4">Item 4</asp:ListItem>
<asp:ListItem Value="Value 5" Selected="True">Item 5</asp:ListItem>
<asp:ListItem Value="Value 6">Item 6</asp:ListItem>
</asp:ListBox>
</td><td>
<asp:button Text="--->" OnClick="AddBtn_Click" runat="server" /><br>
<asp:button Text="<---" OnClick="DelBtn_Click" runat="server" />
</td><td>
<asp:ListBox id=ListBox2 Width="100px" runat="server"/>
</td></tr>
</table>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<html>
<head>
<script runat="server">
void AddBtn_Click(Object Sender, EventArgs e)
{
if (ListBox1.SelectedIndex > -1) //检查是否有选中项,否则会报错!未将引用指向对象实列
{
if (ListBox2.Items.FindByValue(ListBox1.SelectedItem.Text) == null) //如果2中未存在选中的值
{
ListItem Item = new ListItem();
// Text and Value are swapped.
Item.Text = ListBox1.SelectedItem.Value;
Item.Value = ListBox1.SelectedItem.Text;
ListBox2.Items.Add(Item);
}
}
}
void DelBtn_Click(Object Sender, EventArgs e)
{
if (ListBox2.SelectedIndex > -1) //检查是否有选中项,否则会报错!未将引用指向对象实列
{
ListBox2.Items.Remove(ListBox2.SelectedItem);
}
}
</script>
</head>
<body>
<h3>ListItem Example</h3>
<p>
<form runat=server>
<table>
<tr><td>
<asp:ListBox id=ListBox1 Width="100px" runat="server">
<asp:ListItem Value="Value 1">Item 1</asp:ListItem>//一种添加方式
<asp:ListItem Value="Value 2">Item 2</asp:ListItem>
<asp:ListItem Value="Value 3">Item 3</asp:ListItem>
<asp:ListItem Value="Value 4">Item 4</asp:ListItem>
<asp:ListItem Value="Value 5" Selected="True">Item 5</asp:ListItem>
<asp:ListItem Value="Value 6">Item 6</asp:ListItem>
</asp:ListBox>
</td><td>
<asp:button Text="--->" OnClick="AddBtn_Click" runat="server" /><br>
<asp:button Text="<---" OnClick="DelBtn_Click" runat="server" />
</td><td>
<asp:ListBox id=ListBox2 Width="100px" runat="server"/>
</td></tr>
</table>
</form>
</body>
</html>