I have a LoginForm component. I want to check before submit, that both loginName and password is set. I tried with this code (a lot of stuff omitted):

class LoginForm extends Component {



  constructor() {

    super();



    this.state = {

      error: ,



      loginName: ,

      password: ,

      remember: true

    };

  }





  submit(e) {

    e.preventDefault();

    if(!this.state.loginName || !this.state.password) { //this is null

      this.setState({ error: Fill in both fields });

    } else {

      console.log(submitting form);

    }

  }



  render() {

    return (

      <div className=col-xs-12 col-sm-6 col-md-4>

        <form className=login onSubmit={this.submit}>

          <button type=submit className=btn btn-default>Sign in</button>

        </form>

      </div>

    );

  }

}



export default LoginForm;

however, i get a TypeError in the event handler, saying that this is null.

What should I be doing?