react中的受控组件与非受控组件

非受控组件：现用现取

<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8" />
    <title>react中的受控组件与非受控组件</title>
    <script src="https://unpkg.com/react@18/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/@babel/standalone@7/babel.min.js"></script>
    <script src="https://unpkg.com/prop-types@15.8.1/prop-types.js"></script>
</head>

<body>
    <div id="root"></div>

    <script type="text/babel">
        const root = ReactDOM.createRoot(document.getElementById('root'));
        class MyComponent extends React.Component {
            sevaDate = (e) => {
                const { name, password } = this;
                alert(`用户名：${name.value}，密码：${password.value}`);
            }
            render() {
                return (
                    <form onSubmit={this.sevaDate}>
                        <input type="text" ref={c => this.name = c}></input>
                        <input type="password" ref={c => this.password = c}></input>
                        <button type="submit">提交</button>
                    </form>
                );
            }
        };
        root.render(<MyComponent />);

    </script>
</body>

</html>

受控组件

类似于vue中的数据双向绑定

<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8" />
    <title>react中的受控组件与非受控组件</title>
    <script src="https://unpkg.com/react@18/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/@babel/standalone@7/babel.min.js"></script>
    <script src="https://unpkg.com/prop-types@15.8.1/prop-types.js"></script>
</head>

<body>
    <div id="root"></div>

    <script type="text/babel">
        const root = ReactDOM.createRoot(document.getElementById('root'));
        class MyComponent extends React.Component {
            state = {
                name: '',
                password: ''
            }
            sevaDate = (e) => {
                e.preventDefault();// 阻止表单提交的默认行为
                alert(`用户名：${this.name}，密码：${this.password}`);
            }
            sevaName = (e) => {
                this.name = e.target.value; // 将输入框的值赋值给state中的name
            }
            sevaPassword = (e) => {
                this.password = e.target.value; // 将输入框的值赋值给state中的password
            }
            render() {
                return (
                    <form onSubmit={this.sevaDate}>
                        <input type="text" onChange={this.sevaName}></input>
                        <input type="password" onChange={this.sevaPassword}></input>
                        <button type="submit">提交</button>
                    </form>
                );
            }
        };
        root.render(<MyComponent />);

    </script>
</body>

</html>

总结

尽量少写非受控组件因为受控组件里一个ref都没有（官方建议少用ref）