10 表单.md

Forms

简单例子

• App.jsx

import React from 'react';

class App extends React.Component {

   constructor(props) {
      super(props);

      this.state = {
         data: 'Initial data...'
      }
   };

   updateState = (e) => {
      this.setState({data: e.target.value});
   }

   render() {
      return (
         <div>
            <input type = "text" value = {this.state.data}
               onChange = {this.updateState} />
            <h4>{this.state.data}</h4>
         </div>
      );
   }
}

export default App;

• main.js

import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.jsx';

ReactDOM.render(<App/>, document.getElementById('app'));

复杂例子

• App.jsx

import React from 'react';

class App extends React.Component {

   constructor(props) {
      super(props);

      this.state = {
         data: 'Initial data...'
      }

   };

   updateState = (e) => {
      this.setState({data: e.target.value});
   }

   render() {
      return (
         <div>
            <Content myDataProp = {this.state.data}
               updateStateProp = {this.updateState}></Content>
         </div>
      );
   }
}

class Content extends React.Component {

   render() {
      return (
         <div>
            <input type = "text" value = {this.props.myDataProp}
               onChange = {this.props.updateStateProp} />
            <h3>{this.props.myDataProp}</h3>
         </div>
      );
   }
}
export default App;

• main.js

import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.jsx';

ReactDOM.render(<App/>, document.getElementById('app'));