STRING

1.Stringni consolega chiqarish yo'llari

with " "
with ' '
with ``

let str1 = "Hello world";
let str2 = 'Hello world';
let str3 = `Hello world`;
console.log(str1);
console.log(str2);
console.log(str3);

//Differneces
let str1 = "Hello 'wor'ld" // "" ichida '' ishlatsak mumkin
let str2 = 'Hello "wor"ld' // '' ichida "" ishlatish mumkin
let name = "Jamshidbek";
let str3 = `Hello world ${name}`; //backtick bilan string ichiga js kod 
//yoza olamiz va chiqadigan stringni dynamic qila olamiz

2.Special characters

\ - shu belgi kelsa ozidan keyingi barcha narsani ignore qiladi va keyingi qatordan kod yozsak ishlaydi;
\n - new line ga kodni otkazadi;
\t - tab tashlab qoyadi.

let str1 = "Hello \ 
'world'";
console.log(str1) 

let str2 = "Hello \n world"
console.log(str2) 
s
let str3 = "Hello \t world"
console.log(str3)

3.New String - yangi string xosil qiladi.

let str1 = "Hello world"
let str2 = newString("Hello world");
console.log(str2=="Hello world")

4.Accessing chars -stringga murojaat qilish

by Index[ ] - only positive numbers
by .at - can get +,- values
by charAt

let str1 = "Hello world";
console.log(str1[1]); //birinchi indexni chiqaradi
console.log(str1[-1])//minus qiymat qabul qilmagani uchun undefined qaytadi
console.log(str1.at(-1))// minus qiymat qabul qiladi
console.log(str1.charAt(1));

5.Methods

length - stringni uzuligini chiqaradi;
toUpperCase() - stringni hamma harfini kattaga aylantiradi;
toLowerCase() - stringni hamma harfini kichikka aylantiradi;
indexOf() - stringda nechanchi indexdan boshlanganini chiqaradi;
includes()- string ichida siz qidirgan so'z bormi yoki yoq;
startsWith()-string kiritgan so'zingizdan boshlanadimi yo'qmi;
endsWith() - string kiritgan so'zingiz bilan tugaydimi yo'qmi;
padEnd();
padStart();
slice()- kesib olish indexdan indexgacha, includes + - values;
substring() - kesib olish, swipe greater value, not include - values;
substr() - birinchi parametr nechanchi indexdan boshlab kesib olish, ikkinchi index nechta element kesib olish;
eval() - string ichida arifmetik amallarni bajarishga imkon beradi;
trim() - stringdagi bo'sh joylarni kesib tashlaydi;
trimEnd() - oxiridan bo'sh joylarni kesib tashlaydi;
trimStart() - boshidan bo'sh joylarni kesib tashlaydi;
split() - stringlarni array ko'rinishida ajrtatish;
concat()- stringlarni bir biriga qo'shish uchun ishlatiladi;
replace() - stringni boshqa bir stringga almashtirish;

//length
let str1 = "Hello world";
console.log(str1.length);

//toUpperCase()
let str1 = "Hello world";
console.log(str1.toUpperCase());

//toLowerCase() 
let str1 = "Hello world";
console.log(str1.toLowerCase());

//indexOf and lastIndexOf 
let str1 = "Hello world";
console.log(str1.indexOf("l")); // l stringni 3 ni elementida 
let str2 = "Hello world";
console.log(str2.indexOf("l",5));// 5-indexdan boshlab qidirish
let str3 = "Hello world";
console.log(str3.indexOf("l")); // oxiridan qidirib keladi

//includes()
let str1 = "Hello world";
console.log(str1.includes("l"));

//startsWith()
let str1 = "Hello world";
console.log(str1.startsWith("He"));
console.log(str1.startsWith("wo"));

//endsWith()
let str1 = "Hello world";
console.log(str1.endsWith("lo"));
console.log(str1.endsWith("ld"));

//padEnd()
let str1 = "Hello world";
console.log(str1.padEnd(20, "+"));
console.log(str1.padEnd(30, "."));

//padStart()
let str1 = "Hello world";
console.log(str1.padStart(10, ".")); 

//slice()
let str1 = "Hello world";
console.log(str1.slice(0))//all
console.log(str1.slice(0,5)); // 0 to 5-indexgacha not include 5-index
console.log(str1.slice(0,-2); //orqadan kesadi

//substring()
let str1 = "Hello world";
console.log(str1.substring(0,6))
console.log(str1.substring(0,-2)); // not includes - value
console.log(str1.slice(7,2)); //swipe greater value

//substr()
let str1 = "Hello world";
console.log(str1.substr(2,2));

//eval()
console.log(eval(`2+2`));
console.log(eval(`2*2`));
console.log(eval(`2+2*2`));

//split()
let str1 = "Hello world";
console.log(str1.split("")) // har bir elementni donalab chiqarib beradi
console.log(str1.split(" ")) // bo'sh joyni topadi va ajratadi
console.log(str1.split("o")) // o harfini bor joyda ikkiga ajratadi

//concat()
let str1 = "Hello";
console.log(str1.concat("world")); // output: Hello world

//replace() 
let str1 = "Hello world, how is it going?"
console.log(str1.replace("world", "developer"));

6. Loop in strings

let str = "Hello world";
for(char of str){
  console.log(char)
}