Optimize OR in IF

Question

I have a code like this:

if (action == \'John\' || action == \'John Beckham\' || action == \'Henry John\'){
     alert(\'true!\');
}

How do I m

Answer 1

Try this, it uses indexOf:

if (['a', 'b', 'c', 'd', 'e'].indexOf(action) > -1) {
  alert(true);
}

Update: If you want to support IE7 and below, use the answer to this question

If you're using jQuery, you can use $.inArray like this:

if ($.inArray(action, ['a','b','c','d') > -1) {
  alert(true);
}

UPDATE

You can also use a regexp with test (The group makes the regexp not match "John Langhammerer" / actions with extra chars to the ones to be matched):

if ((/^(John Langhammer|Piet Krauthammer|Some Guy)$/i).test(action)) {
  alert(true);
}

UPDATE: /i makes the regexp case insensitive.

Below is a solution which would have worked for one-char actions:

You can also use String.indexOf which is supported in IE7 (if your actions are all one char):

if ('abcde'.indexOf(action) > -1) {
  alert(true);
}