vue日期时间选择器

需要实现同时选择日期和时间，并且能够方便的赋初始值

html

<el-form-item label="日期时间">
<el-date-picker v-model="form.selectDatetime" type="datetime" placeholder="选择时间" 
@change="dataSearch" value-format="yyyy-MM-dd HH:mm" format="yyyy-MM-dd HH:mm"></el-date- 
picker>
</el-form-item>

js

dataSearch() {
     this.getListByDataTime();
},
async initData(data) {
     //获取当前时间
     var now   = new Date();
     var monthn = now.getMonth()+1;
     var yearn  = now.getFullYear();
     var dayn = now.getDate();
     var h = now.getHours();
     var m =now.getMinutes();
     var s = now.getSeconds();
     this.form.selectDatetime = yearn+"-"+monthn+"-"+dayn+" "+h+":"+m+":"+s;
     this.getListByDataTime();
},
async getListByDataTime(data) {

},

初始赋值

this.$set(this.form, 'selectDatetime', '2020-03-03 03:00');