陣營propType無法讀取的屬性未定義

Question

使用propTypes驗證道具提供了以下錯誤：

TypeError: Cannot read property 'string' of undefined.

TypeError: Cannot read property 'func' of undefined.

有問題的代碼是在片段的底部：

import React from 'react'; 
import ProjectItem from './ProjectItem'; 

class Projects extends React.Component { 

    deleteProject(title) { 
     this.props.onDelete(title); 
    } 

    render() { 
     let projectItems; 

     if (this.props.project) { 
     projectItems = this.props.project.map(project => { 
      return (
       <ProjectItem key={project.title} project={project} onDelete={this.deleteProject.bind(this)} /> 
      ) 
     }); 
     } 

     return (
     <div className="Projects"> 
      {projectItems} 
     </div>  
    );  
    } 

} 

Projects.propTypes = { 
    projects: React.PropTypes.string, 
    onDelete: React.PropTypes.func 
} 

Answer 1

您需要安裝prop-types包，然後添加進口語句

import PropTypes from prop-types;

位於班級的頂部。

The PropTypes have been moved from React to their own package prop-types.

編輯：由於在評論中提到的，這是隻適用於陣營15.5及以上版本。