<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<script type="text/javascript">
function test(){
$("wc").val("1111");
}
</script>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form action="${pageContext.request.contextPath }/login" method="post">
用户<input id="wb" type="text" name="name" onFocus="test()"/><span id="wc"></span><br/>
密码<input type="password" name="password"/><br/>
<input type="submit" value="提交"/>
</form>
</body>
</html>
就是想让后边出现一行字提示要输入的账号的格式
没有获得焦点之前可以先将id为wc的标签隐藏，获得焦点之后再将其展示
$("#wc").show()和$("#wc").hide()
也可以是$("#wc").css("display","none")和$("#wc").css("display","block")
$("#wc").val("1111");