ECMAScript6/basic-js.html at master · mhsunny/ECMAScript6 · GitHub

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<!DOCTYPE html>
<html>

<body>

    <h2>JavaScript Class</h2>

    <p>In this example we demonstrate a simple class definition and how to use it.</p>
    <code>
        class Car {
            constructor(brand) {
                this.carname = brand;
            }
        }
        class Motor {
            constructor(name) {
                this.motorname = name;
            }
        }

        mymotor = new Motor("General Motor");
        mycar = new Car("Ford");

        document.getElementById("demo").innerHTML = mymotor.motorname;
    </code>

    <p id="demo"></p>

    <script>
        class Car {
            constructor(brand) {
                this.carname = brand;
            }
        }
        class Motor {
            constructor(name) {
                this.motorname = name;
            }
        }

        mymotor = new Motor("General Motor");
        mycar = new Car("Ford");

        document.getElementById("demo").innerHTML = mymotor.motorname;
    </script>

    <h2>Array.find()</h2>


    <p id="demo2"></p>

    <script>
        var numbers = [4, 9, 16, 25, 29];
        var first = numbers.find(myFunction);

        document.getElementById("demo2").innerHTML = "First number over 18 is " + first;

        function myFunction(value, index, array) {
            return value > 18;
        }
    </script>

    <h2>Number Object Properties</h2>

    <p>MIN_SAFE_INTEGER</p>

    <p id="demo3"></p>
    <p>MAX_SAFE_INTEGER</p>

    <p id="demo4"></p>
    <script>
        var y = Number.MIN_SAFE_INTEGER;
        var x = Number.MAX_SAFE_INTEGER - 1;
        document.getElementById("demo4").innerHTML = x;
        document.getElementById("demo3").innerHTML = y;
    </script>


    <h2>JavaScript Number Methods</h2>

    <p>The isInteger() method returns true if the argument is an integer.</p>
    <p>Otherwise it returns false.</p>
    Number.isInteger(10) + "<br>" + Number.isInteger(10.5);
    <p id="demo5"></p>

    <script>
        document.getElementById("demo5").innerHTML =
            Number.isInteger(10) + "<br>" + Number.isInteger(10.5);
    </script>

    <h2>JavaScript Number Methods</h2>

    <p>The isSafeInteger() method returns true if the argument is a safe integer.</p>
    <p>Otherwise it returns false.</p>
    Number.isSafeInteger(10) + "<br>" + Number.isSafeInteger(12345678901234567890);

    <p id="demo6"></p>

    <script>
        document.getElementById("demo6").innerHTML =
            Number.isSafeInteger(10) + "<br>" + Number.isSafeInteger(12345678901234567890);
    </script>

    <h2>JavaScript Number Methods</h2>

    <p>The isFinite() method returns false if the argument is Infinity or NaN.</p>
    <p>Otherwise it returns true.</p>
    isFinite(10 / 0) + "<br>" + isFinite(10 / 1);

    <p id="demo7"></p>

    <script>
        document.getElementById("demo7").innerHTML =
            isFinite(10 / 0) + "<br>" + isFinite(10 / 1);
    </script>

    <h2>The ** Operator</h2>

    <p id="demo8"></p>

    <script>
        var x = 10;
        document.getElementById("demo8").innerHTML = x ** 2;
    </script>


    <h2>JavaScript Array.forEach()</h2>

    <p>Calls a function once for each array element.</p>
    var txt = "";</br>
    var numbers = [45, 4, 9, 16, 25];</br>
    numbers.forEach(myFunction);</br>
    document.getElementById("demo10").innerHTML = txt;</br>
    function myFunction(value) {</br>
    txt = txt + value + "<br>"; }
    </br>
    <p id="demo10"></p>

    <script>
        var txt = "";
        var numbers = [45, 4, 9, 16, 25];
        numbers.forEach(myFunction);

        document.getElementById("demo10").innerHTML = txt;

        function myFunction(value) {
            txt = txt + value + "<br>";
        }
    </script>


    <h2>JavaScript Array.filter()</h2>

    <p>Creates a new array with all array elements that passes a test.</p>

    <p id="demo12"></p>

    <script>
        var numbers = [45, 4, 9, 16, 25];
        var over18 = numbers.filter(myFunction);

        document.getElementById("demo12").innerHTML = over18;

        function myFunction(value, index, array) {
            return array;
        }
    </script>

    <h2>JavaScript Array.reduce()</h2>

    <p>This example finds the sum of all numbers in an array:</p>
    var sum = numbers.reduce(myFunction)<br> document.getElementById("demo").innerHTML = "The sum is " + sum
    <br> function myFunction(total, value, index, array) {<br> return total + value<br> }
    <br>
    <p id="demo13"></p>

    <script>
        var numbers = [45, 4, 9, 16, 25];
        var sum = numbers.reduce(myFunction);

        document.getElementById("demo13").innerHTML = "The sum is " + sum;

        function myFunction(total, value, index, array) {
            return total + value;
        }
    </script>

    <h2>JavaScript Array.every()</h2>

    <p>The every() method checks if all array values pass a test.</p>

    <code>
        var numbers = [45, 4, 9, 16, 25];
        var allOver18 = numbers.every(myFunction);

        document.getElementById("demo14").innerHTML = "All over 18 is " + allOver18;

        function myFunction(value, index, array) {
            return value > 18;
        }
    </code>


    <p id="demo14"></p>

    <script>
        var numbers = [45, 4, 9, 16, 25];
        var allOver18 = numbers.every(myFunction);

        document.getElementById("demo14").innerHTML = "All over 18 is " + allOver18;

        function myFunction(value, index, array) {
            return value > 18;
        }
    </script>


    <h2>JavaScript Array.indexOf()</h2>

    <p id="demo15">/p>

        <script>
            var fruits = ["Apple", "Orange", "Apple", "Mango"];
            var a = fruits.indexOf("Orange");
            document.getElementById("demo15").innerHTML = "Orange is found in position " + a;
        </script>

        <h2>Create Object from JSON String</h2>
        <code>
            var txt = '{"name":"John", "age":30, "city":"New York"}'
            var obj = JSON.parse(txt);
            document.getElementById("demo16").innerHTML = obj.name + ", " + obj.age;
        </code>

        <p id="demo16"></p>

        <script>
            var txt = '{"name":"John", "age":30, "city":"New York"}'
            var obj = JSON.parse(txt);
            document.getElementById("demo16").innerHTML = obj.name + ", " + obj.age;
        </script>


        <h2>Create JSON string from a JavaScript object.</h2>
        <code>
            var obj = {
                name: "John",
                age: 30,
                city: "New York"
            };
            var obj2 = {
                name: "sunny",
                age: 30,
                city: "NY"
            };
            var myJSON = JSON.stringify(obj2);
            document.getElementById("demo17").innerHTML = myJSON;
        </code>

        <p id="demo17"></p>

        <script>
            var obj = {
                name: "John",
                age: 30,
                city: "New York"
            };
            var obj2 = {
                name: "sunny",
                age: 30,
                city: "NY"
            };
            var myJSON = JSON.stringify(obj2);
            document.getElementById("demo17").innerHTML = myJSON;
        </script>


        <h2>ES6 and Variable Hoisting</h2>
        <code>
            var main = function() {
                for (var x = 0; x < 5; x++) {
                    console.log(x);
                }
                console.log("x can be accessed outside the block scope x value is :" + x);
                console.log('x is hoisted to the function scope');
                document.getElementById("demo18").innerHTML = x;
            }
            main();
        </code>
        <p id="demo18"></p>

        <script>
            var main = function() {
                for (var x = 0; x < 5; x++) {
                    console.log(x);
                }
                console.log("x can be accessed outside the block scope x value is :" + x);
                console.log('x is hoisted to the function scope');
                document.getElementById("demo18").innerHTML = x;
            }

            main();
        </script>

        <h2>No binding of arguments
        </h2>

        <p id="demo19"></p>


        <script>
            function foo(n) {
                var f = (...args) => args[0] + n;
                return f(10);
            }

            num = foo(1); // 11
            document.getElementById("demo19").innerHTML = num;
            console.log(num);
        </script>

        <h2>Arrow functions used as methods</h2>
        <p>As stated previously, arrow function expressions are best suited for non-method functions. Let's see what
        </p>

        'use strict';<br> var obj = { // does not create a new scope<br> i: 10,<br> b: () => console.log(this.i, this),<br> c: function() {<br> console.log(this.i, this);<br> }
        <br> }
        <br>
        <br> obj.b(); // prints undefined, Window {...} (or the global object)<br> obj.c(); // prints 10, Object {...}<br>


        <script>
            'use strict';

            var obj = { // does not create a new scope
                i: 10,
                b: () => console.log(this.i, this),
                c: function() {
                    console.log(this.i, this);
                }
            }

            obj.b(); // prints undefined, Window {...} (or the global object)
            obj.c(); // prints 10, Object {...}
        </script>


        <h2>The Function Constructor
        </h2>

        var func = new Function("x", "y", "return x*y;"); <br> function product() { <br> var result; <br> result = func(10,20); <br> console.log("The product : "+result)<br> } product()

        <script>
            var func = new Function("x", "y", "return x*y;");

            function product() {
                var result;
                result = func(10, 20);
                console.log("The product : " + result)
            }
            product();
        </script>


</body>

</html>