text: import React, { Component } from 'react';
  import {Link} from 'react-router-dom';
  import {
      Navbar,
      NavbarBrand,
      NavbarToggler,
      Collapse,
      Nav,
      NavItem,
      NavLink,
      UncontrolledDropdown,
      DropdownToggle,
      DropdownMenu,
      DropdownItem
  } from 'reactstrap';
  
  class NavHeader extends Component {
  
      state = {
          isOpen: false
      };
      toggle = this.toggle.bind(this);
  
      toggle() {
          this.setState({
              isOpen: !this.state.isOpen
          })
      }
  
      render() {
          return <Navbar color="dark" dark expand="md">
              <NavbarBrand href="/">
                  <img src="https://cdn.rd.gt/assets/images/global/redgate-logo--white.svg?v=1" width="128" className="d-inline-block align-top" alt="" />
              </NavbarBrand>
              <NavbarToggler onClick={this.toggle} />
              <Collapse isOpen={this.state.isOpen} navbar>
                  <Nav className="ml-auto" navbar>
                      <NavItem>
                          <NavLink href="/">Hello</NavLink>
                      </NavItem>
                      <UncontrolledDropdown nav inNavbar>
                          <DropdownToggle nav caret>
                              World
                          </DropdownToggle>
                          <DropdownMenu right>
                              <DropdownItem ><Link to="/users">Users</Link></DropdownItem>
                              <DropdownItem><Link to="/github">GitHubRender</Link></DropdownItem>
                          </DropdownMenu>
                      </UncontrolledDropdown>
                  </Nav>
              </Collapse>
          </Navbar>;
      }
  }
  
  export default NavHeader;