示例代码如下：
<html>
<head>
<script type="text/javascript" src="/jquery/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$("button").click(function(){
alert("text的值：" + $("#spId").text() + "\n" +
"html的值：" + $("#spId").html() )
$("#spId").text("testSpan")
alert("text的值：" + $("#spId").text() + "\n"+
"html的值：" + $("#spId").html() )
$("#spId").html("<p>testSpantest</p>")
alert("text的值：" + $("#spId").text() + "\n"+
"html的值：" + $("#spId").html() )
});
});
</script>
</head>
<body>
<div><span id="spId"><a href="/go.html?url=#">初期值</a></span></div>
<button>切换</button>
</body>
</html>
<html>
<head>
<script type="text/j
