Javascript call and apply

Function.prototype.apply

Calls a function with a given this value and arguments provided as an array.

syntax:

fun.apply(thisArg[, argsArray]).

thisArg
The value of this provided for the call to fun.

argsArray
An array like object

Example:

/* min/max number in an array */var numbers = [5, 6, 2, 3, 7]; /* using Math.min/Math.max apply */var max = Math.max.apply(null, numbers); /* This about equal to Math.max(numbers[0], ...) or Math.max(5, 6, ..) */var min = Math.min.apply(null, numbers); /* vs. simple loop based algorithm */max = -Infinity, min = +Infinity; for (var i = 0; i < numbers.length; i++) {  if (numbers[i] > max)    max = numbers[i];  if (numbers[i] < min)     min = numbers[i];}

The main difference is that apply lets you invoke the function with arguments as an array; call requires the parameters be listed explicitly.

See here and here .

Pseudo syntax:

theFunction.apply(valueForThis, arrayOfArgs)

theFunction.call(valueForThis, arg1, arg2, ...)