如何将普通的javascript助手类导入React? [英] How to import plain javascript helper classes into React?

问题描述

我有一个用ES6风格编写的React类，例如:

I have a React class that I have written in ES6 style such as:

export default class App extends React.Component {
    constructor(props) {
        super(props);
        let HClass = new HelperClass();
    }        
}

同一个文件中存在的我的帮助器类如下:

And my helper class, which exists within the same file, looks like:

class HelperClass {
    constructor() {
       this.somevar="";
    }

    some_function= () => {
        //do work
    }
 }

但是，当尝试构造和运行'some_function'方法时，我收到TypeErrors指出该函数未定义.

However, when trying to construct and run the 'some_function' method, I receive TypeErrors stating that the function is not defined.

我的问题是:

1. 实例化HelperClass时我做错了什么?
2. 我应该做些类似反应"的事情，而不是这些助手类吗?它们什么也没渲染，但是我需要它们来管理我从ActiveMQ处理的消息.

谢谢！

推荐答案

当前，new HelperClass()仅在构造函数内部可用.您只能在此处使用some_function.

Currently, new HelperClass() is only available inside your constructor. You can use the some_function there only.

通常，您会这样做:

要在特定方法内使用:

// outside the constructor
myMethod() {
  let HClass = new HelperClass();
  HClass.some_function();
}

用于任何方法:

// inside the constructor
this.props.HClass = new HelperClass();

// to call
this.props.HClass.some_function();

或者，简单地使用这个:

Or, simply using this:

// inside the constructor
this.HClass = newHelperClass();

// to call
this.HClass.some_function();

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