表单验证 

<!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>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>

<body>
<select size="1" id="qq" onchange="change()">
<option selected="selected" value="11">汉堡</option>
<option value="22">鸡腿</option>
<option value="33">可乐</option>
</select><br />
<br />
<p id="pp" style="font-size:24px; color:red;">价格：8元</p>

</body>
</html>
<script>
function change()
{
    var a =    document.getElementById("qq").value;
    var p =document.getElementById("pp");
    if(a=="11")
    {
        p.innerHTML="价格：8元";    
    }
    else if(a=="22")
    {
        p.innerHTML="价格：10元";    
    }
    else
    {
        p.innerHTML="价格：3元";    
    }
}
</script>

 

posted @ 2016-06-01 08:44  高和平  阅读(84)  评论(0)    收藏  举报