import React from 'react'; import AppBar from '@material-ui/core/AppBar'; import Toolbar from '@material-ui/core/Toolbar'; import Button from '@material-ui/core/Button'; import Typography from '@material-ui/core/Typography'; import DashboardIcon from '@material-ui/icons/Dashboard'; import IconButton from '@material-ui/core/IconButton'; import {Link} from 'react-router-dom'; import Menu from '@material-ui/core/Menu'; import MenuItem from '@material-ui/core/MenuItem';  class Header extends React.Component {     constructor(props) {         super(props);         this.state = {             anchorEl: null         };     }      handleClick(event)  {         console.log(event);         console.log(this);         this.setState({             anchorEl: event.currentTarget,         });     }      handleClose() {         console.log(342);         this.setState({             anchorEl: null,         });     }      render() {         return (             <AppBar position="static">                 <Toolbar>                     <IconButton edge="start" color="inherit" aria-label="menu">                         <DashboardIcon />                     </IconButton>                     <Button color="inherit">                         <Link to="/home" className="menu-link">                             棣栭〉                         </Link>                     </Button>                     <Button color="inherit" onClick={this.handleClick}>                         <Link to="/home" className="menu-link">                             鍐呭绠＄悊                         </Link>                     </Button>                     <Menu                         id="simple-menu"                         anchorEl={this.anchorEl}                         keepMounted                         open={Boolean(this.anchorEl)}                         onClose={this.handleClose}                     >                         <MenuItem onClick={this.handleClose}>Profile</MenuItem>                         <MenuItem onClick={this.handleClose}>My account</MenuItem>                         <MenuItem onClick={this.handleClose}>Logout</MenuItem>                     </Menu>                 </Toolbar>             </AppBar>         );     } }  export default Header; 

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