尝试分配到只读属性ECMAScript React Native [英] Attempted to assign to readonly property ECMAScript React Native

问题描述

我试图为我的组件中声明的数组赋值。不幸的是，异常被抛出。

  TypeError：尝试分配到只读属性
  / pre> 
 
 
即使我删除 strict 模式，仍然出现异常。可以请人指导我如何使变量既可读又可写？谢谢..！
 
 
 
 代码 
 
 
 
 
  class RootView extends Component {
 
 cachedData：[]; //声明数组
 
 
 //尝试在某些函数中分配字典
 
 someFunction（results）{
 
 this.cachedData [this.state.searchString.length  -  1] =结果; 
 //这里提出的异常
} 
 
} 
  
 
 
解决方案
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; 
} 
} 
  
如果您的透析器支持实验代码（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; 
} 
} 
  
 
I am trying to assign a value to an array declared in my Component. Unfortunately, exception is thrown.
TypeError: Attempted to assign to readonly property
Even if I remove strict mode, still exception is being raised. Can please someone guide me how can I make a variable both readable and writable? Thanks..!

Code:

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
}

}

解决方案
Your syntax is incorrect. Add it to a constructor.
class RootView extends Component {

  constructor() {
    super();
    this.cachedData = [];
  }
  someFunction(results) {
    this.cachedData[this.state.searchString.length - 1] = results;
  }
}
If your transpiler supports experimental code (stage 0), you can use the following:
class RootView extends Component {
  cachedData = [];
  someFunction(results) {
    this.cachedData[this.state.searchString.length - 1] = results;
  }
}


                        
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