*/
@media screen and (max-width: 900px) and (min-width: 600px), (min-width: 1100px) {
div.example {
font-size: 50px;
padding: 50px;
border: 8px solid black;
background: yellow;
}
}
9. INTRODUCE
WITH A PROJECT
GitHub
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GitHub setup environment, creating account, install gitbash,
setups
Nodejs
git
gitbash
2. GitHub termins: master, push, pull, MR, clone
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JAVASCRIPT
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1. JAVASCRIPT – INTRODUCTION - DATA TYPES
• Javascript
• JavaScript compile qilishning yolları (in html,
node console, online js compiler)
• data types (number, str, boolean, undefined, null, array, obj, function) general intro;
• O’zgaruvchilar (var, const, let)
• Numbers ni chuqur tanishtirish (ES6 dagi ozgarishlarni ham)
+, -, /, *, ++, —, %, float, -=, +=, *=, /=,
string as a number
let x = "10";
let y = "20";
let z = x + y; // z will be 1020 (a string) concatenate
Infinity (or -Infinity) is the value JavaScript will return if you calculate a number outside the largest possible number.
let x = 2 / 0; // x will be Infinity
let y = -2 / 0; // y will be -Infinity
By default, JavaScript displays numbers as base 10 decimals.
But you can use the toString() method to output numbers from
base 2 to
base 36.
Hexadecimal is
base 16. Decimal is
base 10. Octal is
base 8.
Binary is base 2.
let myNumber = 32;
myNumber.toString(); // returns “32”
myNumber.toString(32); // returns 10
myNumber.toString(16); // returns 20
myNumber.toString(8); // returns 40
myNumber.toString(2); // returns 100000
let x = 500;
let y = new Number(500);
// (x === y) is false because x and y have different types // objs cant be compared
Number.isInteger(), Number.parseFloat(), Number.parseInt(), num.toFixed()
Number(true); // returns 1
Number(false); // returns 0
Number("10"); // returns 10
Number(" 10"); // returns 10
Number("10 "); // returns 10
Number(" 10 "); // returns 10
Number("10.33"); // returns 10.33
Number("10,33"); //
returns NaN
Number("10 33"); // returns NaN
Number("John"); // returns NaN
Number.isInteger(123) //true
Number.isInteger(-123) //true
Number.isInteger(5-2) //true
Number.isInteger(0) //true
var a = parseFloat("10") //10
var b = parseFloat("10.00") // 10
var c = parseFloat("10.33") // 10.33
var d = parseFloat("34 45 66") // 34
var e = parseFloat(" 60 ") // 60
var f = parseFloat("40 years") // 40
var g = parseFloat("He was 40") // NaN
Number.parseInt(x, base); // base 2, 10 16
Number.parseInt(string)
Number.parseInt(string, radix)
var num = 55,6789;
var n = num.toFixed(2); // 55,67
• NaN qiymati
NaN is a JavaScript reserved word indicating that a number is not a legal number. Trying to do arithmetic with a non-numeric string will result in NaN (Not a Number):
let x = 100 / "Apple"; // x will be NaN (Not a Number)
let x = 100 + "10"; '10010’ // x will be 10
let x = 100 / "Apple";
isNaN(x); // returns true
because x is Not a Number