<HTML>
<HEAD>
<title>点击input文本框，文字消失</title>
<script type="text/javascript">
//得到焦点触发事件
function OnfocusFun(element,elementvalue)
{
if(element.value==elementvalue)
{
element.value="";
element.style.color="#000";
}
}
//离开输入框触发事件
function OnBlurFun(element,elementvalue)
{
if(element.value==""||element.value.replace(/\s/g,"")=="")
{
element.value=elementvalue;
element.style.color="#999";
}
}
</script>
</HEAD>
<body>
<div>点击<strong>输入框</strong>框内文字消失实例</div>
<div>
<span>账号：</span>
<input type="text" value="请输入用户名" id="UserId" onfocus="OnfocusFun(this,\'请输入用户名\')" style="color:#999" onblur="OnBlurFun(this,\'请输入用户名\')"/>
</div>
<div>
<span>密码:</span>
<input type="text" value="请输入密码" id="Password" onfocus="OnfocusFun(this,\'请输入密码\')" onblur="OnBlurFun(this,\'请输入密码\')" style="color:#999"/>
</body>
</HTML