var band={
"name":"the sun",
"members":[
    {
        "name":[{"m":"shide","n":"yes"},{}],
        "role":"taiyang"
    },
    {
        "name":"b",
        "role":"yueliang"
    },
    {
        "name":"c",
        "role":"diqiu"
    }
],
"year":"2009"
}
alert(band.members);
alert(band.members[0].name[0].n)
alert(band.members[0].role)

------解决方案--------------------

<script>

   var ajosn={'name':'test','age':25,'country':'china'};
	alert(ajosn.name);
 </script>
这个就是josn数据，在服务器端echo  json_encode($array);就可以啦