jqgrid显示不了数据解决方案

jqgrid显示不了数据
jqgrid显示不数据，请各位大大帮忙看看



<!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=utf-8" />
<title>无标题文档</title>
<link rel="stylesheet" type="text/css" media="screen" href="css/ui-lightness/jquery-ui-1.8.2.custom.css?3.8.99" />
<link rel="stylesheet" type="text/css" media="screen" href="css/ui.jqgrid.css?3.8.99" />

<script src="js/jquery-1.9.0.min.js?3.8.99" type="text/javascript"></script>
<script src="js/i18n/grid.locale-cn.js?3.8.99" type="text/javascript"></script>
<script src="js/jquery.jqGrid.min.js?3.8.99" type="text/javascript"></script>

<script type="text/javascript">
$(function(){ 
jQuery("#list").jqGrid({
   	url:'dd.php',
	datatype: "json",
	height: 255,
	width: 600,
   	colNames:['编号','名称','主屏尺寸','操作系统','电池容量', '价格(￥)','操作'], //数据列名称（数组）
   	colModel:[ //数据列各参数信息设置
   		{name:'sn',index:'sn', editable:true, width:80,align:'center',title:false,editable: true,edittype:"text"},
   		{name:'title',index:'title', width:180,title:false, editable: true,sorttype:"text"},
   		{name:'size',index:'size', width:120, editable: true,sorttype:"text"},
		{name:'os',index:'os', width:120,editable:true,sorttype:"text"},
   		{name:'charge',index:'charge', width:100,align:'center',editable:true,sorttype:"text"},
		{name:'price',index:'price', width:80,align:'center',editable:true,sorttype:"text"},
   		{name:'opt',index:'opt', width:80, sortable:false, align:'center',editable:true,sorttype:"text"}		
   	],
   	rowNum:50,
	rowTotal: 2000,
	rowList : [20,30,50],
	loadonce:true,
   	mtype: "GET",
	rownumbers: true,
	rownumWidth: 40,
	gridview: true,
   	pager: '#pager',
   	sortname: 'id',
    viewrecords: true,
    sortorder: "asc",
	caption: "Toolbar Searching"	
});

jQuery("#list").jqGrid('navGrid','#pager',{del:false,add:false,edit:false,search:false});
jQuery("#list").jqGrid('filterToolbar',{stringResult: true,searchOnEnter : false});
  
}); 
</script>

</head>
<body>

<table id="list"></table>
<p id="page" ></p>

</body>
</html>


<?PHP

include_once ("connect.php");

	$page = $_GET['page'];
		$limit = $_GET['rows'];
		$sidx = $_GET['sidx'];
		$sord = $_GET['sord'];
		if (!$sidx)
			$sidx = 1;
        $where = '';
        $title = uniDecode($_GET['title'],'utf-8');
        if(!empty($title))
            $where .= " and title like '%".$title."%'";
        $sn = uniDecode($_GET['sn'],'utf-8');
        if(!empty($sn))
            $where .= " and sn='$sn'";

		$result = mysql_query("SELECT COUNT(*) AS count FROM products where deleted=0".$where);
		$row = mysql_fetch_array($result, MYSQL_ASSOC);
		$count = $row['count'];
		//echo $count;
		if ($count > 0) {
			$total_pages = ceil($count / $limit);
		} else {
			$total_pages = 0;
		}
		if ($page > $total_pages)
			$page = $total_pages;
		$start = $limit * $page - $limit;
		if ($start<0) $start = 0;
		$SQL = "SELECT * FROM products WHERE deleted=0".$where." ORDER BY $sidx $sord LIMIT $start , $limit";
		$result = mysql_query($SQL) or die("Couldn t execute query." . mysql_error());

		$responce->page = $page;
		$responce->total = $total_pages;
		$responce->records = $count;
		$i = 0;
		while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
			$responce->rows[$i]['id'] = $row[id];
			$opt = "<a href='#'>修改</a>";
			$responce->rows[$i]['cell'] = array (
				$row['sn'],
				$row['title'],
				$row['size'],
				$row['os'],
				$row['charge'],
				$row['price'],
				$opt
			);
			$i++;
		}
		//print_r($responce);
		echo json_encode($responce);
		
	
		
		
	function uniDecode($str, $charcode) {
	$text = preg_replace_callback("/%u[0-9A-Za-z]{4}/", toUtf8, $str);