Javascript My Array Push 只获取最后一个值

Question

我有一个 for 循环，我想在每个周期增加年份，但我只得到最后一年重复多次。

for (let i = 0; i < 2; i++) {
  this.data.year = new Date().getFullYear() + i;
  this.data.noSolar = averageBill * increaseRate;
  this.data.withSolar = (contractAmount * .004) + customerCharge;
  this.data.saving = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12);
  this.data.check = SREC;
  this.data.total = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12) + SREC;
  this.dataSource.push(this.data);
}

在本例中，年份为2020年显示两次。我想要像2019年和2020年这样的东西。就像变量被多次引用一样。

Answer 1

每次迭代时都应创建一个新对象。您每次都引用相同的对象。

你可以这样做，

for (let i = 0; i < 2; i++) {
  this.dataSource.push({
     year : new Date().getFullYear() + i,
     noSolar : averageBill * increaseRate,
     withSolar : (contractAmount * .004) + customerCharge,
     saving : (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12),
     check : SREC,
     total : (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12) + SREC,
  });
}

或者喜欢，

for (let i = 0; i < 2; i++) {
      this.data=new DataSourceObject();
      this.data.year = new Date().getFullYear() + i;
      this.data.noSolar = averageBill * increaseRate;
      this.data.withSolar = (contractAmount * .004) + customerCharge;
      this.data.saving = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12);
      this.data.check = SREC;
      this.data.total = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12) + SREC;
      this.dataSource.push(this.data);
    }

Answer 2

对象的引用被推送到数组中。而是克隆或创建副本，然后推送

    const temp = {};
    for (let i = 0; i < 2; i++) {
      this.data.year = new Date().getFullYear() + i;
      this.data.noSolar = averageBill * increaseRate;
      this.data.withSolar = (contractAmount * .004) + customerCharge;
      this.data.saving = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12);
      this.data.check = SREC;
      this.data.total = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12) + SREC;
      // this.dataSource.push(...this.data)
      Object.assign(temp, this.data);
      this.dataSource.push(temp);
    };

Answer 3

你可以

试试这个：-

for (let i = 0; i < 2; i++) {
  this.data.year = new Date().getFullYear() + i;
  this.data.noSolar = averageBill * increaseRate;
  this.data.withSolar = (contractAmount * .004) + customerCharge;
  this.data.saving = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12);
  this.data.check = SREC;
  this.data.total = (contractAmount * .004 + customerCharge) * 12 - (averageBill * 12) + SREC;
  this.dataSource.push(Object.assign({}, this.data));
}