Four invocation modes of JS advanced-function

1, object method call pattern method internal this point to the object of the current caller D

Defining classes (constructors)

function Dog (dogname) {

Create an empty object to let the empty object ==this

THIS.name = Dogname;

this.age = 0;

This.run = function () {

Console.log (THIS.name + ' is running ... ')

}

This is returned by default if the function calls (new) as a constructor and no data is returned.

}

var d= new Dog (' Wangwang ');

D.run ();

2. Constructor call mode new

function Cat () {

THIS.name = "Cat"

This.age = 19;

This.run = function () {

Console.log (THIS.name + ' is running ... ')

}

}

var cat = new Cat (); Constructor call pattern

Cat.run ()//method invocation mode

3. Function call mode

function f (A, B) {

Console.log (A + ' +b)

Console.log (this) window

}

F (2,3)

Exercises

function Dog () {

This.age = 19;

Console.log (This)

}

Dog ()//window function call pattern

var d = new Dog (); D Constructor Call pattern

4.

Four invocation modes of JS advanced-function