Function.apply( ): invoke a function as a method of an object — ECMAScript v3


function.apply(thisobj, args)



The object to which function is to be applied. In the body of the function, thisobj becomes the value of the this keyword. If this argument is null, the global object is used.


An array of values to be passed as arguments to function.


Whatever value is returned by the invocation of function.



If this method is invoked on an object that is not a function or if this method is invoked with an args argument that is not an array or an Arguments object.


apply( ) invokes the specified function as if it were a method of thisobj, passing it the arguments contained in the args array. It returns the value returned by the function invocation. Within the body of the function, the this keyword refers to the thisobj object.

The args argument must be an array or an Arguments object. Use ) instead if you want to specify the arguments to pass to the function individually instead of as array elements.


// Apply the default Object.toString( ) method to an object that
// overrides it with its own version of the method. Note no arguments.
// Invoke the Math.max( ) method with apply to find the largest
// element in an array. Note that first argument doesn't matter
// in this case.
var data = [1,2,3,4,5,6,7,8];
Math.max.apply(null, data);

See Also )

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