DevGuru JavaScript METHOD: Function::apply

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			METHOD: Function::apply Function.apply(thisArg[, argArray]) The apply method allows you to call a function and specify what the keyword this will refer to within the context of that function. The thisArg argument should be an object. Within the context of the function being called, this will refer to thisArg. The second argument to the apply method is an array. The elements of this array will be passed as the arguments to the function being called. The argArray parameter can be either an array literal or the deprecated arguments property of a function. The apply method can be used to simulate object inheritance as in the following example. We first define the constructor for an object called Car which has three properties. Then the constructor for a second object called RentalCar is defined. RentalCar will inherit the properties of Car and add one additional property of its own - carNo. The RentalCar constructor uses the apply method to call the Car constructor, passing itself as thisArg. Therefore, inside the Car function, the keyword this actually refers to the RentalCar object being constructed, and not a new Car object. By this means,the RentalCar object inherits the properties from the Car object. Code: function Car(make, model, year) { this.make = make; this.model = model; this.year = year; } function RentalCar(carNo, make, model, year) { this.carNo = carNo; Car.apply(this, new Array(make, model, year)) } myCar = new RentalCar(2134,"Ford","Mustang",1998) document.write("Your car is a " + myCar.year + " " + myCar.make + " " + myCar.model + ".") Output: Your car is a 1998 Ford Mustang. NOTE: The apply method is very similar to the call method and only differs in that, up until now, you could use the deprecated arguments array as one of its parameters.