Restrict entry to alphanumeric characters and space for Ion Input in Ionic

Ionic Framework ionic-v3
4

Try:

  public onKeyUp(event: any) {

    let newValue = event.target.value;

    let regExp = new RegExp('^[A-Za-z0-9? ]+$');

    if (! regExp.test(newValue)) {
      event.target.value = newValue.slice(0, -1);
    }
  }