<!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=gb2312" />
<title>jquery放大缩小文字</title>
<script type="text/javascript" src="js/jquery-1.3.1.js"></script>
<script type="text/javascript">
$(function(){
   $("span").click(function(){
    var theSize = $("#title").css("font-size");
    var theTitleSize =parseFloat(theSize,10);//获取字体的大小
    var units = theSize.slice(-2); //获取单位
    var c_name = $(this).attr("class");//获取属性
    if(c_name =="c_big"){//如果是放大则增大文字
       if(theTitleSize <= 22){//判断大小，如果小于22px则减少
          theTitleSize+=2;
          }
    }else if(c_name =="c_small"){//如果是缩小则缩小文字
       if(theTitleSize >= 12){//判断大小，如果大于12px则减少
          theTitleSize-=2;
          }
    }
    $("#title").css("font-size",theTitleSize + units);//添加样式
    });
});
</script>
<style type="text/css">
#content{
    width:300px;
    height:450px;
    background:#000000;
}
.c_big{
    width:30px;
    height:15px;
    background:#00F;
    border:1px;
    margin:20px 20px;
}
.c_small{
    width:30px;
    height:15px;
    background:#00F;
    border:1px;
    margin:10px 20px;
}
#title{
color:#FFFFFF;
}
</style>
</head>

<body>
<div id="content">
<div id="content_caption"><span class="c_big">放大</span><span class="c_small">缩小</span></div>
<div>
<p id="title">举得起放得下的叫举重，举得起放不下的叫负重。可惜，大多数人的爱情，都是负重的。
If you can hold something up and put it down, it is called weight-lifting; if you can hold something up but can never put it down,it's called burden-bearing. Pitifully, most of people are bearing heavy burdens when they are in love.
</p></div>
</div>
</body>
</html>