$('#tt').css("color","red"); if(document.getElementById("tt")){... 

 
<!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>
    <title></title>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
</head>
<body>
    <div>test</div>
    <script type="text/javascript">
        if(document.getElementById("tt")){
           document.getElementById("tt").style.color="red";
        }
    </script>
</body>
</html>


<!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>
    <title></title>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <!--   引入jQuery -->
    <script src="../../scripts/jquery.js" type="text/javascript"></script>
</head>
<body>
    <div id="tt">test</div>
    <script type="text/javascript">
        $('#tt').css("color","red");
    </script>
</body>
</html>

 

posted @ 2017-10-17 16:46  sky20080101  阅读(45)  评论(0)    收藏  举报