我们有一个初始状态为禁用且选中的复选框。然后在客户端通过JavaScript启用它。如果用户取消选中该复选框并按下按钮以调用回发,则复选框的状态在服务器端仍然保持选中状态。这显然是不希望发生的行为。以下是示例。
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="testcb.aspx.cs" Inherits="ESC.testcb" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<script type="text/javascript">
function buttonClick() {
var cb = document.getElementById('<%= CheckBox1.ClientID %>');
cb.disabled = false;
cb.parentNode.disabled = false;
}
</script>
<div>
<asp:CheckBox ID="CheckBox1" runat="server" Checked="true" Enabled="false" />
<asp:Button ID="Button1" runat="server" Text="Button" OnClientClick="buttonClick(); return false;" />
<asp:Button ID="Button2" runat="server" Text="Button2" OnClick="button2Click" />
</div>
</form>
</body>
</html>
还有服务端代码:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace ESC
{
public partial class testcb : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void button2Click(object sender, EventArgs e)
{
string h = "";
}
}
}
所以我们在“string h”行处中断,检查CheckBox1.Checked的值。它是true,即使在表单上未选中。