Ext "查询" 按钮定向传递参数

buttons:[{
              text: "查询",
              handler: function () {
                  querystore.proxy = new Ext.data.HttpProxy({
        url: 'findShipmentByJson'
      });
      var pagesize = {start:0,limit:commonPageSize}
      var params = Ext.applyIf(queryform.form.getValues(),pagesize);
      querystore.load({
          params: params
      });
              },
              formBind: true
          }