014.React中收集表单数据-一一网

非受控组件

对于所有输入组件，现用现取为非受控组件这类组件一般较多使用ref

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <!-- 准备好容器 -->
    <div id="test"></div>
    <!-- 引入依赖 ,引入的时候，必须就按照这个步骤-->
    <script type="text/javascript" src="../js/react.development.js"></script>
    <script type="text/javascript" src="../js/react-dom.development.js"></script>
    <script type="text/javascript" src="../js/babel.min.js"></script>
    
    <!--这里使用了babel用来解析jsx语法-->
    <script type="text/babel">
        class Login extends React.Component{
            //现用现取为非受控组件
            handleSubmit=()=>{
                event.preventDefault()
                console.log('this',this)
                const {username,password} = this
                console.log(`用户名是${username.value},密码是${password.value}`)
            }
            render(){
                return(
                    <form onSubmit={this.handleSubmit}>
                        用户名<input ref={c=>this.username = c} type="text" name="username"/>
                        密码  <input ref={c=>this.password = c} type="password" name="password"/>
                        <button>登录</button>
                    </form>
                )
            }
        }

        ReactDOM.render(<Login/>,document.getElementById('test'))
    </script>
</body>
</html>
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受控组件

随着输入维护状态是受控组件一般较多使用oChange事件,ref有性能上的缺陷推荐使用受控组件。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <!-- 准备好容器 -->
    <div id="test"></div>
    <!-- 引入依赖 ,引入的时候，必须就按照这个步骤-->
    <script type="text/javascript" src="../js/react.development.js"></script>
    <script type="text/javascript" src="../js/react-dom.development.js"></script>
    <script type="text/javascript" src="../js/babel.min.js"></script>
    
    <!--这里使用了babel用来解析jsx语法-->
    <script type="text/babel">
        class Login extends React.Component{
            // 初始化状态
            state={
                username:'',
                password:'',
            } 
            // 随着输入维护状态是受控组件 ref有性能上的缺陷 推荐使用受控组件
            handleSubmit=()=>{
                event.preventDefault()
                console.log('this',this)
                const {username,password} = this.state
                console.log(`用户名是${username},密码是${password}`)
            }
            userNameChange=(e)=>{
                console.log(e.target.value);
                this.setState({username:e.target.value})
            }
            passwordChange=(e)=>{
                console.log(e.target.value);
                this.setState({password:e.target.value})
            }
            render(){
                return(
                    <form onSubmit={this.handleSubmit}>
                        用户名<input onChange={this.userNameChange} type="text" name="username"/>
                        密码  <input onChange={this.passwordChange} type="password" name="password"/>
                        <button>登录</button>
                    </form>
                )
            }
        }

        ReactDOM.render(<Login/>,document.getElementById('test'))
    </script>
</body>
</html>
复制代码