Question

I want to create function that can be used either with Id or by passing jQuery object.

var $myVar = $('#myId');

myFunc($myVar);
myFunc('myId');

function myFunc(value)
{
    // check if value is jQuery or string
}

How can I detect what kind of argument was passed to the function?

Note! This question is not same. I don’t want to pass selector string like #id.myClass. I want to pass the jQuery object like in the example.

Answer 1

Use the typeof operator

if ( typeof value === 'string' ) {
  // it's a string
} else {
  // it's something else
}

Or to make really sure it’s an instance of the jQuery object

if ( typeof value === 'string' ) {
  // it's a string
} else if ( value instanceof $) {
  // it's a jQuery object
} else {
  // something unwanted
}