登录（学习笔记）

//这是一个组件<div className="login_btn center">  <Button   style={{width:'100%',height:'42px',backgroundColor: '#fff',color: '#03030'}}   title="登录"   onClick={this.loginEvent.bind(this)}/></div>

<div     onClick={() => this.props.onClick && this.props.onClick()}    className="button center"     style={this.props.style}>    { this.props.title || '默认按钮' }</div>

//点击登录loginEvent() {    //路径 我这里写的是一部分路径    let url = "/admin/login";    let form = new FormData();    let username;    let password;    var _this = this;    //当用户名和密码在本地存储时，执行getUserInfo()    localStorage.getItem('username') && localStorage.getItem('password') && getUserInfo()    //此函数的作用是，取出localStorage存储的用户名和密码    getUserInfo(){        username = localStorage.getItem('username');        password = localStorage.getItem('password');    }    //得不到用户名和密码任何一个时，就执行dealUserInfo函数    (!localStorage.getItem('username) || !localStorage.getItem('password')) && dealUserInfo()    //得到初始化的用户名和密码    dealUserInfo(){        username = _this.state.username;        password = _this.state.password;    }    form.append('username',username);    form.append('password',password);    return fetch(url,{        method: 'POST',        body: form    }).then(res=>{        //        localStorage.setItem('jwt_token',data.headers.get('jwt_token'));        return res.json()    }).then(data=>{        //        loalStorage.getItem('user',JSON.stringify(data));        if(data.enabled){            localStorage.getItem("username",this.state.username);            localStorage.getItem("password",this.state.password);            this.props.history.replace('/home');        }    })}

进入登录页面时，获取密码

getLocalStorage(){    var username = localStorage.getItem('username');    var password = localStorage.getItem('password');    username && password && this.setState({        username: username,        password: password    })}

componentDidMount(){    this.getLocalStorage()}