实现类似facebook无刷新ajax更新

<script type="text/javascript">
$(document).ready(function()
{

$('.edit_link').click(function()
{
$('.text_wrapper').hide();
var data=$('.text_wrapper').html();
$('.edit').show();
$('.editbox').html(data);
$('.editbox').focus();
});

$(".editbox").mouseup(function()
{
return false
});

$(".editbox").change(function()
{
$('.edit').hide();
var boxval = $(".editbox").val();
var dataString = 'data='+ boxval;
$.ajax({
type: "POST",
url: "update_profile_ajax.php",
data: dataString,
cache: false,
success: function(html)
{
$('.text_wrapper').html(boxval);
$('.text_wrapper').show();

}
});

});

$(document).mouseup(function()
{
$('.edit').hide();
$('.text_wrapper').show();
});

});
</script>
<style type="text/css">
body
{
font-family:Arial, Helvetica, sans-serif;

font-size:12px;
}
.mainbox
{
width:250px;
margin:50px;
}
.text_wrapper
{
border:solid 1px #0099CC;
padding:5px;
width:187px;



}
.edit_link
{
float:right
}
.editbox
{
overflow: hidden; height: 61px;border:solid 1px #0099CC; width:190px; font-size:12px;font-family:Arial, Helvetica, sans-serif; padding:5px
}
</style>
<div>
<a href="#" title="Edit">Edit</a>
<?php
include("db.php");
$sql=mysql_query("select email from users where user_id='1'");
$row=mysql_fetch_array($sql);
$profile=$row['email'];
?>
<div><?php echo $profile; ?></div>

<div><textarea cols="23" rows="3"></textarea></div>
</div>