[JS] 11. This

11_This.html

<script>
//If the function is invoked using Function.call() or Function.apply(), 
//this will be set to the first argument passed to .call()/.apply(). 
//If the first argument passed to .call()/.apply() is null or undefined, 
//this will refer to the global object (which is the window object in web browsers).

//A function invoked using Function call()
var myObject ={
    sayHello: function(){
        console.log("Hi! My Name is "+this.myName);    
    },
    myName: "Rebecca"
    };
    
var secondObject = {
    myName: "Colin"
};

myObject.sayHello(); // "Hi! My name is Rebecca"
myObejct.sayHello.call(secondObject); //"Hi! My name is Colin"
//call()은 메서드 호출, bind() 메서드를 새롭게 만들어 리턴

//A function created using Function.bind()
var myName = "the global obejct";
var sayHello = function(){
    console.log("Hi! My name is " + this.myName);
};
var myObject ={
    myName: "Rebecca"
};
var myObjectHello = sayHello.bind(myObject);
sayHello(); //"Hi! My name is the global object"
myObejctHello(); //"Hi! My name is Rebecca"

//A function being attached to an object at runtime.
var myName = "the global object";
var sayHello = function(){
    console.log("Hi! My name is "+this.myName);
};
var myObject = {
        myName: "Rebecca"
};
var secondObject ={
        myName: "Colin"
};
myObject.sayHello = sayHello;
secondObject.sayHello = sayHello;
sayHello(); // "Hi My name is the global object"
myObject.sayHello(); //"Hi! My name is Colin"

var myNamespace = {
        myObject: {
            sayHello: function(){
                console.log("Hi! My name is "+this.myName);
            },
            myName: "Rebecca"
        }
};
var obj = myNamespace.myObject;
obj.sayHello(); // "Hi My name is Rebecca"
</script>