JS-Practice/08-objects.html at main · MrRahimie/JS-Practice · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Objects</title>
</head>
<body>
    <script>
        /*
        //object
        const product = {
            //property : value
            name : 'socks',
            price : 1090
        };

        console.log(product);
        console.log(product.name);

        //add new object's property
        product.newProperty = true;
        console.log(product);

        //delete property
        delete product.newProperty;
        console.log(product);
        */


        /* LESSONS 2

        const product2 = {
            name : 'shirt' ,
            //because - will be detect as minus
            'delivery-time' : 12,
            //nested
            rating: {
                stars : 4.5,
                count : 87
            },
            fun : function function1(){
                console.log('function is also a value');
            }
        };
        console.log(product2['name']);
        console.log(product2['delivery-time']);
        console.log(product2.rating.count);
        product2.fun();

        Java Script Object Notation
        - send data btween computers
        - store data

        //JSON built-in objects (syntax)
        //do not support function as object's attb

        //convert JS Object to JSON <<JSON.stringify>>
        console.log(JSON.stringify(product2)); <-- save object in string

        //convert JSON to JS Object <<JSON.parse>>
        const jsonString = JSON.stringify(product2);
        console.log (JSON.parse(jsonString));

        //local storage (does not delete data after refresh page)

        */

        //AUTO-BOXING
        console.log('hello'.length);
        console.log('hello'.toUpperCase());

        const object1 = {
            message : 'hello',
        };

        //copy reference (object is reference)
        const object2 = object1;

        object1.message = 'NICE TRY';
        console.log(object1);
        console.log(object2);

        const object3 = {
            message : 'NICE TRY',

        };
        //objects are reference (not compare value)
        console.log(object1 === object3);
        console.log(object1 === object2);

        //shortcut object
        const object4 = {
            message : 'NICE TRY',
            price : 321
        };

        //const message = object4.message
        //take out property out of object
        const {message , price} = object4;
        console.log(message);
        console.log(price);

        const object5 = {
            //message : message
            //shorthand property
            message,
            //shorthand fx
            method(){
                console.log('method');
            }
        };

        console.log(object5);
        object5.method();

    </script>
</body>
</html>