KVData到底应该怎么定义啊？

kvdata多个key时应该怎么写啊？~~
我这么写会报错，说“KVDataList must be an Array”

 let kvdata =new Array();
                         let  data1={key:rankString,value:this.rankScore};
                         let  data2={key:rankTimeString,value:date.getTime()};
                         kvdata.push(data1);
                         kvdata.push(data2);
                         wx.setUserCloudStorage(kvdata);