JavaScript with profit
index.html file
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<h1 id="someText"><h1>
<script src="home.js"></script>
</body>
</html>
home.js file
alert('this is sayed');
console.log("Hello World");
var a = "hey dear";
console.log(a);
var b = 3423;
console.log(b);
let age = prompt("what is your age? ")
document.getElementById('someText').innerHTML = "your age is: "+ age;
Function in JS
function fun() {
alert("this is a function.");
console.log("This is a function 2")
};
fun();
function greeting(){
let name = prompt("what is your name?");
result = "Hello! "+ name;
console.log(result);
}
greeting();
// how do arguments work in functions
// How do we add 2 numbers together in a function?
function sumNumbers(num1, num2) {
let result = num1 + num2;
console.log(result);
}
sumNumbers(22,33);
function greeting(yourName){
let result = "Hello " + yourName;
console.log(result);
}
let name = prompt("what is your name?");
greeting(name);
While loops
// while loops
var num = 0;
while (num < 100){
num += 1;
console.log(num);
}
For loops
// For loops
for(let num = 0; num < 100; num++){
console.log(num);
}
Data types in JS
// Datatypes
let yourAge = 18; // number
let yourName = "Bob Marley"; // string
let name = {first: "Jo", last:"Job Current"}; // object
let truthh = false; // boolean
let fruits = ["Apple", "Banana","Graps"]; // array
let random; // undefined
let nothing = null; // value null
Strings in JavaScript (common method)
// String in JavaScript (common methods)
let fruit = "Banana";
let moreFruits = "Bananana\nApple";
console.log(fruit.length);
console.log(fruit.indexOf("nan"));
Array in JS
// Array
let fruits = ["Banana", "Apple","Orange","Pine Apple"];
// Another way to create an array
let cities = new Array("Japan","Malaysia", "Singapore","Hong Kong");
// alert(fruits[3]);
// fruits[3] = "Peer";
// console.log(fruits);
// for(let i = 0; i < fruits.length; i++){
// console.log(fruits[i]);
// }
// // Array common methods
// console.log("to string: " ,fruits.toString());
// console.log(fruits.join("-"))
// console.log(fruits.join("*"))
// console.log(fruits);
// console.log(fruits, fruits.pop(), fruits);
// console.log(fruits.push("Blackberry"),fruits);
// console.log(fruits.push("Pomogrant"));
// console.log(fruits,fruits.shift());
// console.log(fruits.shift() + "\nAfter removed\n"+ fruits);
let vegetable = ['Asparagus',"Tomato","Broccoli"];
let allVegetable = fruits.concat(vegetable); // combine array
// console.log(allVegetable);
// slicing array
// console.log(allVegetable.slice(1,4));
// Reverse array
// console.log(allVegetable.reverse());
console.log(allVegetable.sort());
let number = [2,4,5,64,3,44,36,1,9,8];
// console.log(number.sort());
console.log(number.sort(function(a,b){return a-b})) // sorted in accending order
console.log(number.sort(function(a,b){return b-a})) // sorted in deccending order
let emptyArray = new Array();
for(let num= 0; num <= 10; num++){
emptyArray.push(num)
}
console.log(emptyArray);
Objects in JS
// Objects in Javascript
// Dictonaries in Python
let student = {
first: "Rafeh",
Last: "Qazi",
age: 23,
height:170,
studentInfo: function (){
return this.first + "\n" + this.Last + "\n" +this.age;
}
};
console.log(student);
console.log(student.Last);
console.log(student.first);
student.first = "No Rafeh"; // change value
console.log(student.first);
student.age+=3;
console.log(student.age);
console.log(student.studentInfo());
JSON file
[
{
"name": "Cyed",
"age": 26,
"height": 170
},
{
"name": "Chauli",
"age": 98,
"height": 150
}
]
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<script>
let student = `[
{
"name": "Cyed",
"age": 26,
"height": 170
},
{
"name": "Chauli",
"age": 98,
"height": 150
}
]`
console.log(student);
console.log(JSON.parse(student));
console.log(JSON.parse(student)[0]);
console.log(JSON.parse(student)[0].name);
console.log(JSON.parse(student)[1].age);
</script>
</body>
</html>
output:
[
{
"name": "Cyed",
"age": 26,
"height": 170
},
{
"name": "Chauli",
"age": 98,
"height": 150
}
Array [ {…}, {…} ]
0: Object { name: "Cyed", age: 26, height: 170 }
1: Object { name: "Chauli", age: 98, height: 150 }
length: 2
<prototype>: Array []
Object { name: "Cyed", age: 26, height: 170 }
age: 26
height: 170
name: "Cyed"
<prototype>: Object { … }
Cyed
98