如下所示：
复制代码代码如下：
<！Doctype HTML公共“ - // W3C // DTD XHTML 1.0 Transitional // en”“” http://www.org/tr/tr/xhtml1/dtd/xhtml1-xhtml1-transitional.transitional.dtdd'>
<html xmlns =“ http://www.w3.org/1999/xhtml”>
<头>
<meta http-equiv =“ content-type” content =“ text /html; charset = utf-8” />
<title>无标题文档</title>
<style type =“ text/css”>
.clearfieldblurred {
颜色：#ccc;
字体风格：斜体；
字体重量：正常；
宽度：150px;
}
.ClearFieldActive {
颜色：＃4E4E4E;
字体重量：大胆；
宽度：150px;
}
</style>
<脚本类型=“ text/javascript”>
函数clearfiled（）{
var bbb = document.getElementById（“ bbb”）;
if（bbb.value ==“ bbb”）{
bbb.value ='';
bbb.ClassName ='ClearFieldActive';
}
}
window.document.onmousedown = function（）{
var bbb = document.getElementById（'bbb'）;
if（bbb.value ==“”）{
bbb.value ='bbb';
bbb.classname ='clearfieldblurred';
}
}
</script>
</head>
<身体>
<input type =“ text” id =“ aaa” value =“ aaa” onfocus =“ if（this.value =='aaa'）{this.value =''; this.className ='clear fieldActive';} =“ if（this.value ==''）{this.value ='aaa'; this.className ='clearfieldblurred';}/>
<br />
<输入type =“ text” id =“ bbb” value =“ bbb” onclick =“ clearfiled（）” />
</body>
</html>