ahmarsuhail

const user = {
    name: "Ahmar",
    keys: [1, 2, 3],
    printName: function() {
        this.keys.forEach(function(x) {
            console.log(this.name);
        }, this)
    }
}

ahmarsuhail

const user = {
    name: "Ahmar",
    keys: [1, 2, 3],
    printName: function() {
        this.keys.forEach(function(x) {
            console.log(this.name);
        })
    }
}

ahmarsuhail

const user = {
    name: "Ahmar",
    keys: [1, 2, 3],
    printName: function() {
        this.keys.forEach((x) => {
            console.log(this.name);
        })
    }
}

ahmarsuhail

const user = {
    name: "Ahmar",
    printName: () => {
        console.log(this.name);
    }
  }

user.printName(); //Outputs: Undefined

ahmarsuhail

class User {
    constructor(name) {
        this.name = name;
    }

    printName() {
        console.log(this.name);
    }
}

ahmarsuhail

const user = {
    name: "Ahmar",
    printName: function() {
        console.log(this.name);
    }
  }

const printNameOutsideOfObject = user.printName
const boundFunction = printNameOutsideOfObject.bind(user);
boundFunction(); //Outputs: Ahmar

ahmarsuhail

const printNameOutsideOfObject =  function() {
        console.log(this.name);
    }
printNameOutsideOfObject(); //The "this" here refers to the global window object, and not the user object.   

ahmarsuhail

const user = {
    name: "Ahmar",
    printName: function() {
        console.log(this.name);
    }
  }

const printNameOutsideOfObject = user.printName
printNameOutsideOfObject(); //Error, cannot read property of undefined.

ahmarsuhail

const user = {
    name: "Ahmar",
    printName: function() {
        console.log(this.name);
    }
  }

user.printName(); //Outputs: "Ahmar"