EXTJs GridPanel不显示信息

  <script type="text/javascript">

       Ext.onReady(function () {

           var proxy = new Ext.data.HttpProxy({ method: 'GET', url: 'Handler.ashx' });

           var reader = new Ext.data.JsonReader({}, [

                                    { name: 'CI_No' },

                                    { name: 'CI_Name' },

                                    { name: 'CI_Phone'}]);

           alert("reader:" + reader);

           var store = new Ext.data.Store({

               proxy: proxy, reader: reader

           });

           store.load();

           alert("store:" + store);

           var grid = new Ext.grid.GridPanel({

               store: store,

               columns: [

                { id: 'CI_No', header: "分类ID", width: 250, sortable: true, dataIndex: 'CI_No' },

                { header: "分类名称", width: 75, sortable: true, dataIndex: 'CI_Name' },

                { header: "排序号", width: 75, sortable: true, dataIndex: 'CI_Phone'}],

               height: 350,

               width: 600,

               title: '基本网格示例',

               viewConfig: { columnsText: '显示列', sortAscText: '升序', sortDescText: '降序' }

           });

           grid.render('grid-example');

           grid.getSelectionModel().selectFirstRow();

       });

</script>

{"customerList":[

{"CI_No":"4419580906","CI_Name":"撒旦撒","CI_Phone":"137587895"},

{"CI_No":"1048982471","CI_Name":"撒旦撒","CI_Phone":"137587895"},

{"CI_No":"4073571809","CI_Name":"撒旦撒","CI_Phone":"137587895"}]}