jQuery EasyUI学习教程之datagrid点击列表头排序

<table id="tt" class="easyui-datagrid" style="width:600px;height:250px" 
url="datagrid8_getdata.php" 
title="Load Data" iconCls="icon-save" 
rownumbers="true" pagination="true"> 
<thead> 
<tr> 
<th field="itemid" width="80" sortable="true">Item ID</th> 
<th field="productid" width="80" sortable="true">Product ID</th> 
<th field="listprice" width="80" align="right" sortable="true">List Price</th> 
<th field="unitcost" width="80" align="right" sortable="true">Unit Cost</th> 
<th field="attr1" width="150">Attribute</th> 
<th field="status" width="60" align="center">Stauts</th> 
</tr> 
</thead> 
</table> 

$page = isset($_POST['page']) ? intval($_POST['page']) : 1; 
$rows = isset($_POST['rows']) ? intval($_POST['rows']) : 10; 
$sort = isset($_POST['sort']) ? strval($_POST['sort']) : 'itemid'; 
$order = isset($_POST['order']) ? strval($_POST['order']) : 'asc'; 
$offset = ($page-1)*$rows; 
$result = array(); 
include 'conn.php'; 
$rs = mysql_query("select count(*) from item"); 
$row = mysql_fetch_row($rs); 
$result["total"] = $row[0]; 
$rs = mysql_query("select * from item order by $sort $order limit $offset,$rows"); 
$items = array(); 
while($row = mysql_fetch_object($rs)){ 
array_push($items, $row); 
} 
$result["rows"] = $items; 
echo json_encode($result);