JunPyoL22

function price() {
	return this.price;
}

function howMuchIsIt() {
	var ans = "It's "  + price.call( this ) + ' worth';
	console.log( ans );
}

var productA = {

JunPyoL22

var obj = {
  x:10,
  printX:function(){
    console.log(this.x);
  }
}

var printx1 = obj.printX;
printx1() // => undefined
var printx2 = printx1.bind(obj)

JunPyoL22

var indirect = { name: 'indirect function invocation' };  
function concatName(string) {  
  console.log(this === indirect); // => true
  return string + this.name;
}
// Indirect invocations
concatName.call(indirect, 'Hello ');  // >> 'Hello indirect function invocation'  
concatName.apply(indirect, ['Bye ']); // >> 'Bye indirect function invocation'

JunPyoL22

function thisAtConstructorInvoke() {
  console.log(this instanceof thisAtConstructorInvoke); // >> true
  this.property = "default value";
}

var instance = new thisAtConstructorInvoke(); 
instance.property; // >> default value

JunPyoL22

var methodInvoke = {
  des : "calling function owned by object",
  mean : function() {
    console.log(this===window);
    console.log('method invocation is a ' + this.des);
  }
}

var seperated_method = methodInvoke.mean
seperated_method() // >> true, 'method invocation is a undefined'

JunPyoL22

var methodInvoke = {
  des : "calling function owned by object",
  mean : function() {
    console.log(this===methodInvoke);
    console.log('method invocation is a ' + this.des);
  }
}

methodInvoke.mean(); // >> true, method invocation is a calling function owned by object

JunPyoL22

function thisAtfunctionInvoke(){
    console.log(this===window);
    this.number = 20
}

thisAtFunctionInvoke(); // >> true
console.log(window.number===20); // >> true
console.log(this === window); // >> true

JunPyoL22

function thisAtfunctionInvokeInStrictMode(){
    'use strict';
    console.log(this===undefined);
    this.number = 20
}

thisAtfunctionInvokeInStrictMode(); // >> true
console.log(window.number===20); // >> false