easyui datagrid 加载php的数组

<script type="text/javascript">

$('#tt').datagrid({  
    url:null,  
    border:false,
    fit:true,
    fitColumns:true,
    pagination:true,  
    pageSize:20,  
    pageNumber:1,  
    rownumbers:true,
    singleSelect:false,
}); 

var data = <?php echo json_encode($data);?>;
$('#tt').datagrid('loadData',data);

</script>

<table id="tt">
<thead>
     <tr>
          <th data-options="field:'Time',width:20">时间</th>
          <th data-options="field:'status',width:10">操作</th>
          <th data-options="field:'contents',width:60">内容</th>
     </tr>
</thead>
</table>