Categories

callbacks.has()

Categories: Callbacks Object

callbacks.has( callback )Returns: Boolean

Description: Determine whether a supplied callback is in a list

  • callbacks.has( callback )

    version added: 1.1

    callback   The callback to search for.

Example

Using callbacks.has() to check if a callback list contains a specific callback:

// a sample logging function to be added to a callbacks list
var foo = function( value1, value2 ){
    console.log( 'Received:' + value1 + ',' + value2 );
}

// a second function which will not be added to the list
var bar = function( value1, value2 ){
    console.log( 'foobar');
}

var callbacks = $.Callbacks();

// add the log method to the callbacks list
callbacks.add( foo );

// determine which callbacks are in the list

console.log( callbacks.has( foo ) ); // true
console.log( callbacks.has( bar ) ); // false