Passing string parameter into constructor to call function

Question

I have come across this programming style where: Instead of calling an object method directly, they pass in its constructor method a string, the constructor method then check this string and call the function associate with it.

function MySimpleObject(option){
  if (typeof option === 'String'){
    pluginMethods[String].apply(this, arguments);
  }
  else {
    init();
  }
}

This seem to be used with jQuery as extend function a lot.

jQuery.fn.extend({simpleObj: MySimpleObject});

I would really appreciate if someone could enlighten me on this.

Which part are you not sure about? And shouldn't your code snippet there be `pluginMethods[option].apply(this, arguments);`? — Matt Burland, Nov 04 '14 at 20:59
Does this help: http://stackoverflow.com/questions/4968406/javascript-property-access-dot-notation-vs-brackets — Matt Burland, Nov 04 '14 at 21:00

score 1 · Accepted Answer · answered Nov 04 '14 at 20:59

This allows the following style of programming, which is used by jQuery UI for example:

$('selector').datepicker('option', 'option-name', 'option-value');

If you call .datepicker() with no arguments or an object, it initializes the datepicker. When the first argument is a string, it's a call to a method of the datepicker. This approach is used for all the jQuery UI widgets, and is common among many other jQuery plugins as well.

Passing string parameter into constructor to call function

1 Answers1