Simple understanding of call and apply in JavaScript

The ability to target images in JavaScript was added later, for compatibility, so there were a lot of strange things,

functionAnimal () { This. Name = "Animal";  This. ShowName =function() {alert ( This. Name); }    }      functionCat () { This. Name = "Cat"; }       varAnimal =NewAnimal (); varCat =NewCat (); //using the call or Apply method, the ShowName () method that originally belonged to the animal object is given to the object cat. //The input result is "Cat"Animal.showName.call (Cat, ","); //animal.showName.apply (cat,[]); 

So, you can see that call and apply are meant to change this dynamically, and when an object does not have a method, but the others, we can use call or apply to manipulate other objects.

The DOM node chosen by document.getElementsByTagName is a type of array that is similar to array. It cannot apply methods such as Push,pop under the array. We can do this by:
var domnodes = Array.prototype.slice.call (document.getElementsByTagName ("*"));
This allows the domnodes to apply all the methods under the array.

Simple understanding of call and apply in JavaScript