TypeError: counters.indexOf is not a function in React list

Question

我有一个处于 class 状态的列表，当调用单击事件时，我需要从列表中获取选定的组件。这是我的代码

class Counters extends Component {
  state = {
    counters: [
      { id: 1, value: 0 },
      { id: 2, value: 2 },
      { id: 3, value: 2 },
      { id: 4, value: 3 }
    ]
  };

  handleIncrement = counter => {
    const counters = { ...this.state.counters };
    console.log(counter); //this returns when this triggerrd {id: 2, value: 2}
    const index = counters.indexOf(counter);
};

Answer 1

您正在将数组的值复制到对象中。

const counters = [...this.state.counters]