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@@ -0,0 +1,73 @@
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+<!DOCTYPE html>
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+<html lang="en">
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+ <head>
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+ <meta charset="UTF-8" />
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+ <meta http-equiv="X-UA-Compatible" content="IE=edge" />
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+ <meta name="viewport" content="width=device-width, initial-scale=1.0" />
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+ <title>条件渲染</title>
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+ <script src="../../babel.min.js"></script>
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+ <script src="../../react.development.js"></script>
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+ <script src="../../react-dom.development.js"></script>
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+ </head>
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+ <body>
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+ <div id="root"></div>
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+ <script type="text/babel">
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+ function App() {
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+ return (
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+ <div className="app">
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+ <div className="app-header">
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+ {/* <LoginTpl user={{ name: '大侠' }} /> */}
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+ <LoginTpl />
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+ </div>
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+ </div>
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+ );
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+ }
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+
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+ // function LoginTpl({ user }) {
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+ // return user ? (
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+ // <span>您好，{user.name} </span>
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+ // ) : (
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+ // <span>
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+ // 您好，请登录。<button>登录</button>
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+ // </span>
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+ // );
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+ // }
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+
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+ class LoginTpl extends React.Component {
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+ constructor() {
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+ super();
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+ const token = sessionStorage.getItem('token');
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+ this.state = {
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+ token,
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+ user: token ? JSON.parse(sessionStorage.getItem('user')) : {},
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+ };
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+
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+ this.onLogin = this.onLogin.bind(this);
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+ }
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+ onLogin() {
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+ sessionStorage.setItem('token', '123456');
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+ sessionStorage.setItem('user', JSON.stringify({ name: 'daxia' }));
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+
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+ this.setState({
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+ token: '123456',
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+ user: { name: 'daxia' },
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+ });
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+ }
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+
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+ render() {
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+ let { token, user } = this.state;
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+ return token ? (
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+ <span>您好，{user.name} </span>
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+ ) : (
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+ <span>
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+ 您好，请登录。<button onClick={this.onLogin}>登录</button>
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+ </span>
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+ );
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+ }
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+ }
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+
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+ const root = ReactDOM.createRoot(document.querySelector('#root'));
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+ root.render(<App />);
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+ </script>
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+ </body>
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+</html>
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大侠