<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="ITO博客.WebForm1" %>
<!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">
<script src="Js/Jquery1.7.js" type="text/javascript"></script>
<title></title>
<script type="text/javascript">
function exam() {
if (document.getElementById('TextBox1').value == "") {
$('#span').append('<a>不能为空的！</a>');
return false;
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox><span id="span"></span>
<%--应该注意，在按钮的OnClientClick事件为“return exam()”刚刚写好的JS--%>
<asp:Button ID="Button1" runat="server" Text="Button" OnClientClick="return exam()" onclick="Button1_Click" />
</div>
</form>
</body>
</html>