easyui combobox默認選中項

今天寫前端代碼發現combobox還挺難搞，

$("#select_Dic").combobox({
                        url: "http://www.cnblogs.com/Ajax/sys/WebServiceBase.ashx?Method=GetRefItems", //獲取所有私有域
                        valueField: "Code",
                        textField: "Name",
                        panelHeight: "auto",
                        editable: false, //不允許手動輸入
                        onLoadSuccess: function () { //數據加載完畢事件
                            var data = $('#select_Dic').combobox('getData');
                            if (data.length > 0) {
                                $("#select_Dic").combobox('select', data[0].value);
                            }
                        }
                    });