Question

我正在尝试为我Component中声明的数组赋值。不幸的是，抛出异常。

TypeError: Attempted to assign to readonly property

即使我删除strict模式，仍然会引发异常。可以请某人指导我如何使变量既可读又可写？谢谢..！

代码：

class RootView extends Component {

  cachedData : []; //declared array here


//trying to assign dictionary in some function

someFunction(results) {

    this.cachedData[this.state.searchString.length - 1] = results;
    //exception raised here
}

}

Answer 1

您的语法不正确。将其添加到构造函数中。

class RootView extends Component {

  constructor() {
    super();
    this.cachedData = [];
  }
  someFunction(results) {
    this.cachedData[this.state.searchString.length - 1] = results;
  }
}

如果您的转发器支持experimental code（第0阶段），您可以使用以下内容：

class RootView extends Component {
  cachedData = [];
  someFunction(results) {
    this.cachedData[this.state.searchString.length - 1] = results;
  }
}

尝试分配给只读属性ECMAScript React Native

1 个答案: