javascript ReactJS“类型错误：无法读取未定义的属性‘数组’”

ReactJS "TypeError: Cannot read property 'array' of undefined"

提问by Harsh Patel

While running this code I got error on the first line on App.propTypes

运行此代码时，我在第一行出现错误 App.propTypes

TypeError: Cannot read property 'array' of undefined

类型错误：无法读取未定义的属性“数组”

Code:

代码：

  class App extends React.Component {
   render() {
      return (
         <div>
            <h3>Array: {this.props.propArray}</h3>
            <h3>Array: {this.props.propBool ? "true" : "false"}</h3>
            <h3>Func: {this.props.propFunc(3)}</h3>
            <h3>Number: {this.props.propNumber}</h3>
            <h3>String: {this.props.propString}</h3>
            <h3>Object: {this.props.propObject.objectName1}</h3>
            <h3>Object: {this.props.propObject.objectName2}</h3>
            <h3>Object: {this.props.propObject.objectName3}</h3>
         </div>
      );
   }
}


App.propTypes = {
   propArray: React.PropTypes.array.isRequired, //I got error over here
   propBool: React.PropTypes.bool.isRequired,
   propFunc: React.PropTypes.func,
   propNumber: React.PropTypes.number,
   propString: React.PropTypes.string,
   propObject: React.PropTypes.object
}

App.defaultProps = {
   propArray: [1,2,3,4,5],
   propBool: true,
   propFunc: function(e){return e},
   propNumber: 1,
   propString: "String value...",

   propObject: {
      objectName1:"objectValue1",
      objectName2: "objectValue2",
      objectName3: "objectValue3"
   }
}

I tried to search but I didn't get the correct solution.

我试图搜索，但没有得到正确的解决方案。

回答by Agney

Prop-Types are now a separately maintained library named prop-typesHere is the explanation from react-docs: https://reactjs.org/docs/typechecking-with-proptypes.html

Prop-Types 现在是一个单独维护的库，名为prop-types这里是 react-docs 的解释：https: //reactjs.org/docs/typechecking-with-proptypes.html

You have to import them as

您必须将它们导入为

import React from 'react';
import PropTypes from 'prop-types'

class App extends React.Component {
  //App here
}

App.propTypes = {
 propArray: PropTypes.array.isRequired, 
 propBool: PropTypes.bool.isRequired,
 propFunc: PropTypes.func,
 propNumber: PropTypes.number,
 propString: PropTypes.string,
 propObject: PropTypes.object
}

NPM Package

NPM 包

回答by Nitin Singh

Change this:

改变这个：

App.propTypes = {
   propArray: React.PropTypes.array.isRequired, //I got error over here
   propBool: React.PropTypes.bool.isRequired,
   propFunc: React.PropTypes.func,
   propNumber: React.PropTypes.number,
   propString: React.PropTypes.string,
   propObject: React.PropTypes.object
}

to:

到：

App.propTypes = {
  propArray: PropTypes.array.isRequired,
  propBool: PropTypes.bool.isRequired,
  propFunc: PropTypes.func,
  propNumber: PropTypes.number,
  propString: PropTypes.string,
  propObject: PropTypes.object
}`

回答by harun ugur

You should change React.PropTypes.array.* to PropTypes.array.*

您应该将 React.PropTypes.array.* 更改为 PropTypes.array.*

App.propTypes = {
   propArray: PropTypes.array.isRequired,
   propBool: PropTypes.bool.isRequired,
   propFunc: PropTypes.func,
   propNumber: PropTypes.number,
   propString: PropTypes.string,
   propObject: PropTypes.object,
  headerProp: PropTypes.string,
  contentProp: PropTypes.string
}
App.defaultProps = {
  headerProp: "Header from props...",
  contentProp:"Content from props...",
  propArray: [1,2,3,4,5],
  propBool: true,
  propFunc: function(e){return e},
  propNumber: 1,
  propString: "String value...",

  propObject: {
   objectName1:"objectValue1",
   objectName2: "objectValue2",
   objectName3: "objectValue3"
  }
}

回答by palsrealm

The React package no longer contains PropTypes. You need to install the prop-typespackage and

React 包不再包含 PropTypes。您需要安装该prop-types软件包并

import PropTypes from 'prop-types';

Edit: As stated in the first paragraph in the documentation

编辑：如文档第一段所述

React.PropTypes has moved into a different package since React v15.5. Please use the prop-types library instead.

自 React v15.5 以来，React.PropTypes 已移入不同的包中。请改用 prop-types 库。