在方法如何取到goodsdata如把20替換成goodsdata.length

   data(){ 
       return{
           data2: this.getMockData(),
           targetKeys2: this.getTargetKeys(),
           goodsdata: []
     }
    }
    mothods
     getMockData () {
    let mockData = []
    for (var i = 0; i <= 20; i++) {
      mockData.push({
        key: i.toString(),
        label: 'Content ' + i,
        // description: 'The desc of content  ' + i
      })
    }
    return mockData
  },