React——受控组件和非受控组件【八】

前言

react中的受控组件和非受控组件

内容

定义一个包含表单的组件,输入用户名密码后, 点击登录提示输入信息

理解

包含表单组件的分类非受控组件,受控组件

非受控组件

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<!--创建"容器"-->
<div id="login"></div>

<!--引入react核心库-->
<script type="text/javascript" src="../js/react.development.js"></script>
<!--引入react-dom,用于支持react操作DOM-->
<script type="text/javascript" src="../js/react-dom.development.js"></script>
<!--引入babel,用于将jsx转js-->
<script type="text/javascript" src="../js/babel.min.js"></script>
<script type="text/babel">
    class Login extends React.Component {

        handleSubmit = (event) => {
            event.preventDefault() //阻止表单提交
            const {username, password} = this
            alert(`你输入的用户名是: ${username.value}, 你输入的密码是: ${password.value}`)
        }

        render() {
            return (
                <div>
                    <form onSubmit={this.handleSubmit}>
                        用户名: <input ref={ c => this.username = c } name="username" type="text"/>
                        密  码: <input ref={ c => this.password = c } name="password" type="password"/>
                        <button>登录</button>
                    </form>
                </div>
            );
        }


    }

    ReactDOM.render(<Login />, document.getElementById('login'))
</script>
</body>
</html>

受控组件

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<!--创建"容器"-->
<div id="login"></div>

<!--引入react核心库-->
<script type="text/javascript" src="../js/react.development.js"></script>
<!--引入react-dom,用于支持react操作DOM-->
<script type="text/javascript" src="../js/react-dom.development.js"></script>
<!--引入babel,用于将jsx转js-->
<script type="text/javascript" src="../js/babel.min.js"></script>
<script type="text/babel">
    class Login extends React.Component {

        state = {
            username: "",
            password: ""
        }

        saveUserName = (event) => {
            this.setState({username:event.target.value})
        }

        savePassword = (event) => {
            this.setState({password:event.target.value})
        }


        handleSubmit = (event) => {
            event.preventDefault() //阻止表单提交
            const {username, password} = this.state
            alert(`你输入的用户名是: ${username}, 你输入的密码是: ${password}`)
        }

        render() {
            return (
                <div>
                    <form onSubmit={this.handleSubmit}>
                        用户名: <input onChange={this.saveUserName} name="username" type="text"/>
                        密  码: <input onChange={this.savePassword} name="password" type="password"/>
                        <button>登录</button>
                    </form>
                </div>
            );
        }
    }

    ReactDOM.render(<Login />, document.getElementById('login'))
</script>
</body>
</html>

函数柯里化

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<!--创建"容器"-->
<div id="login"></div>

<!--引入react核心库-->
<script type="text/javascript" src="../js/react.development.js"></script>
<!--引入react-dom,用于支持react操作DOM-->
<script type="text/javascript" src="../js/react-dom.development.js"></script>
<!--引入babel,用于将jsx转js-->
<script type="text/javascript" src="../js/babel.min.js"></script>
<script type="text/babel">
    class Login extends React.Component {

        state = {
            username: "",
            password: ""
        }

        saveFormData = (dataType) => {
            return (event) => {
                this.setState({[dataType]:event.target.value})
            }
        }



        handleSubmit = (event) => {
            event.preventDefault() //阻止表单提交
            const {username, password} = this.state
            alert(`你输入的用户名是: ${username}, 你输入的密码是: ${password}`)
        }

        render() {
            return (
                <div>
                    <form onSubmit={this.handleSubmit}>
                        用户名: <input onChange={this.saveFormData('username')} name="username" type="text"/>
                        密  码: <input onChange={this.saveFormData('password')} name="password" type="password"/>
                        <button>登录</button>
                    </form>
                </div>
            );
        }
    }

    ReactDOM.render(<Login />, document.getElementById('login'))
</script>
</body>
</html>
posted @ 2021-02-25 16:58  。思索  阅读(79)  评论(0)  编辑  收藏  举报