javascript - 未处理的 Promise 拒绝 : Cannot read property 'push' of undefined Value

Question

这是我的以下代码:

private convertFormat(src: Array<any>): void {
for (let i of src) {
  this.selectedMonths.push({
    id: i,
    itemName: i
  })
};

this.selectedMonths = JSON.parse(JSON.stringify(this.selectedMonths));
console.log(this.selectedMonths);
}

但是，当我尝试插入已声明的数组 <{}> 时，“.push()”会出现此错误。

Unhandled Promise rejection: Cannot read property 'push' of undefined ; Zone: ; Task: Promise.then ; Value: TypeError: Cannot read property 'push' of undefined

Answer 1

selectedMonths : any[] = [] 在组件类或 ngOnInit this.selectedMonths = [];