DEV Community: Sabrina

String operations

Sabrina — Wed, 16 Oct 2024 13:11:02 +0000

a)Quyidagi kod nima qiladi?

string name = "John";
string upperName = name.ToUpper();
Console.WriteLine(upperName);

b)Stringlarni birlashtirishning bir usulini keltiring.
Javob :
c)Stringlarni solishtirish uchun qaysi metod ishlatiladi?
Javob : Compare

Array

Sabrina — Wed, 16 Oct 2024 12:37:36 +0000

a)Array nima?
Javob : array bu bir necha hil qiymatlardan tashkil topgan malum bir ketma ketlikda joylashgan obyekt.

b)Quyidagi kodning natijasini ayting:

int[] numbers = { 1, 2, 3, 4, 5 };
Console. WriteLine (numbers [2]);

Javob : 3,chunki index 0 dan boshlanadi

OOP

Sabrina — Fri, 11 Oct 2024 15:36:27 +0000

a)Encapsulation - "Inkapsulyatsiya" so'zi lotincha "in capsula" - qobiqda joylashtirish so'zidan olingan. Shundan kelib chiqib inkapsulatsiyani izolyatsiyalash, atrof muhit ta'siridan himoya qilgan holda yopish, himoyalash, biror bir buyum, narsani qolib, kapsulaga solib qo'yish deb tushunish mumkin.

b)Multiple Inheritance bir yoki bir nechta classlardan meros olish degan ma’noda qo’llaniladi.

c) Polimorfizm odatda inkapsulyatsiya va vorislikdan keyin OOP ning uchinchi ustuni deyiladi. Polimorfizm yunoncha so’z bo’lib, “ko’p shaklli” degan ma’noni anglatad

Class Constructor

Sabrina — Fri, 11 Oct 2024 15:20:52 +0000

a) Constructor nima?
Javob : Konstruktor – bu sinfdan obyekt yaratilganda avtomatik ravishda chaqiriladigan maxsus usuldir. U obyektning dastlabki qiymatlarini o'rnatish uchun ishlatiladi. Konstruktor sinf nomi bilan bir xil bo'ladi va u hech qanday qaytarish tipiga ega bo‘lmaydi.

b)Quyidagi kodni to'ldiring :

class Animal
{
   public string Name;
   public Animal(string name)
   {
      Name = name;
   }
}
Animal dog = new Animal("Dog");
Console.WriteLine(dog.Name);

Loops(for while,do while)

Sabrina — Fri, 11 Oct 2024 15:16:54 +0000

a) for loopning sintaksisi qanday?

for(int variable = qiymati, variable = boshqa variable yoki son; increment or decrement;)
{

}

b)while loop va do while o'rtasidagi farq nima?
Javob : do whileda bitta bo'sayam chiqarib beradi,whileda esa xatto bo'lsa hech nima chiqarmidi

c)Quiyidagi kodning natijasini toping :
int i = 0;
while(i < 5)
{
Console.WriteLine(i);
I++;
}
Xatto chunki incrementda I katta harfda yozilgan.Whileni ichida esa i kichkina

Operators(if, else if, else, ternary operator, switch)

Sabrina — Fri, 11 Oct 2024 15:00:38 +0000

a) Quyidagi kodda if, else if, else qismi qanday ishlaydi?

int x = 10;
if (x < 5) 
{
    Console.WriteLine("Less than 5");
} 
else if (x == 10) 
{
    Console.WriteLine("Equal to 10");
} 
else 
{
    Console.WriteLine("Greater than 5");
}

Javob : Agar x qiymati 5dan kam bo'lsa "Less than 5" degan gapni chiqaradi.Agar x qiymati 10ga teng bo'lsa "Equal to 10" degan gapni chiqaradi.Boshqa holatda esa "Greater than 5" chiqaradi

b) Ternary operatorning sintaksisi qanday ?
shart ? ifTrue : ifFalse

c)Quyidagi kodda switch qismida qaysi natija chiqadi?

int day = 3;
 switch (day) 
 {
     case 1:
         Console.WriteLine("Monday");
         break;
     case 2:
         Console.WriteLine("Tuesday");
         break;
     case 3:
         Console.WriteLine("Wednesday");
         break;
     break;

    default:
         Console.WriteLine("Invalid day");
    break;
 }

Value Type va Reference Type

Sabrina — Fri, 11 Oct 2024 14:53:39 +0000

a) Value Type va Reference Type nima?

1. Value Types (Qiymat turlari)
2. Reference Types (Havola turlari)

b) Quyidagi kodni natijasi : 5

int a = 5;
int b = a;
b = 10;
Console.WriteLine(a);

Namespace

Sabrina — Fri, 11 Oct 2024 14:35:25 +0000

a) Namespace nima?

Javob : Bu dasturdagi sinflar mantiqiy guruhlash uchun foydalaniladigan tushuncha.

b) Namespace qanday ishlatiladi?

Namespace ishlatish sintaksisi:
           namespace NamespaceNomi
           {
                // Sinflar, interfeyslar, strukturalar va 
                boshqa elementlar
           }

c) Quyidagi kodni tahlil qiling:

   using System;
   namespace Myname
   {
         class Program
         {
              static void Main(string[] args)
              {
                  Console.WriteLine("Hello World!");
              }
         }
   }

Javob : System kutubxonasini use qilamz,undan keyin namespace yaratiladi.undan keyin console.writeLine() orqali "hello world" degan gapni chiqaramiz.

Data types

Sabrina — Fri, 11 Oct 2024 14:28:59 +0000

a) Quyidagi o'zgaruvchilarni qiymat turlariga ajrating: int,float,string,bool.

int - 4 bayt : -2,147,483,648 dan 2,147,483,647 gacha
float - 4 bayt : ±1.5 x 10^−45 dan ±3.4 x 10^38 gacha
string - Belgilar qatori matnlarni saqlash uchun
bool - (1 bayt) Mantiqiy qiymatlar (true yoki false).

b) float va double orasidagi farq nima?

float = 4 bayt
double esa 8 bayt

Class Object

Sabrina — Fri, 11 Oct 2024 14:11:41 +0000

a) C# da class nima?

Javob : Class - ma'lumotlar to'plami,ya'niy methods,properties.Class object uchun shablondir.

b) Object nima?

JaVob : Object - Classdan yaratilgan konkret nusxadir.

c)Quyidagi kodni natijasi : Tesla

class Car
{
    public string Model;
    public Car(string model)
    {
        Model = model;
    }

}
class Program
{
    static void Main()
    {
Car myCar = new Car("Tesla");
Console.WriteLine(myCar.Model);
    }
}

String methods

Sabrina — Fri, 23 Aug 2024 17:39:42 +0000

Substring() -> returns substring into substring

Console.WriteLine(longstring.Substring(5));
Console.WriteLine(longstring.Substring(5,10));
Console.WriteLine(longstring.Substring(5,10,100));//Error

Error : xatto bo'ladi,sababi - hajmidan oshib ketdi.

Replace() -> replace the specified old character with specified

var longString = "This guy is strongman";
Console.WriteLine(longstring.Replace("is","IS"));
Console.WriteLine(longstring.Replace("very","VERY"));
Console.WriteLine(longstring.Replace("iS","IS", StringComparison.CurrentCultureIgnoreCase));

Join() -> joins the given string using the specified separator;

string [] words = {"apple","banana","cherry"};
string result = string.Join("-",words);
Console.WriteLine(result);

string [] words2 = {"book","pen","notebook"};
string result2 = string.Join("|",words2);
Console.WriteLine(result2);

Remove() -> returns characters from a string
Berilgan tekstdan ochiradi

string tekst = "Hello world";
string tekst1 = tekst.Remove(1,5);
Console.WriteLine(tekst1);

PadLeft() -> returns a string padded with spaces or with specified Unicode character
PadLeft() -> tekstni chap tomonidan nechtadur joy ajratib beradi

string tekst = "Hello world";
string tekst1 = tekst.PadLeft(10,'0');
string tekst2 = tekst.PadLeft(10);
Console.WriteLine(tekst1);
Console.WriteLine(tekst2);

PadRight() -> returns a string padded with spaces or with specified Unicode character
PadRight() -> tekstni ong tomonidan nechtadur joy ajratib beradi

string tekst3 = "Hello world";
string tekst4 = tekst.PadLeft(10,'0');
string tekst5 = tekst.PadLeft(10);
Console.WriteLine(tekst4);
Console.WriteLine(tekst5);

ToCharArray -> converts to string to a char array

string tekst = "Hello";
char [] charArray = tekst.ToCharArray();
foreach(char c in charArray)
{
    Console.WriteLine(c);
}

LastIndexOf() - returns index of the last occurance of specified string

string tekst2 = "Hello world";
int index = tekst2.LastIndexOf("o");
int index2 = tekst2.IndexOf("o");
Console.WriteLine(index);
Console.WriteLine(index2);

Stack and Heap

Sabrina — Tue, 20 Aug 2024 09:48:04 +0000

is string literal mutable or immutable ?

is string variable mutable or immutable ?

string literal - deb " " ichida constanta sifatida yozilgan stringga aytiladi.
string literal immutable - degani bu qiymatni o'zgaritirib bo' lmaydi.

var name = "Ismalali Ustoz";
name = "islamali ustoz";
var son = 15;
son = 16;
Console. WriteLine (name);
Console. WriteLine(son);

Value typelar - stackda saqlanadi
Value type **_deganda, ma' lumotlar tog'ridan- to'g'ri o'zgaruvchida saqlanadi. Bunda o'zgaruvchining qiymati o'zi bilan birga saqlanadi.
_Value typelar** stack xotirasida saqlanadi.
Value typega quydagilar kiradi:
Oddiy turlar - int, float, double, char,bool va h.k;
struct, enum;

int a = 5;
int b = a;
b = 10;
Console.WriteLine(a);
Console-WriteLine(b);

Reference typelar - heapda sagalanadi
Reference type deganda, o' zgaruvchi faqatgina ob'ektning manzilini (reference) saqlaydi, ob'ektning o'zi esa heap (xotiradi) saqlanadi.
Reference typega quydagilar kiradi - class, interface, array(massivlar), delegate.

Stack xotira: Bu juda tez va kichik xotira bo'lib, u qiymatlarni to'g'ridan-to'g'ri o' zgaruvchida saqlaydi.
Value type o' zgaruvchilari stackda saqlanadi.
Stackda saqlangan qlymatlar to'g'ridan-to'g'ri foydalaniladi va o'chiriladi, shuning uchun stack xotira juda samarali.
Heap xotira: Bu katta hajmdagi va nisbatan sekinrog xotira bo'lib, unda ma' lumotlar dinamik ravishda yaratiladi va boshgariladi.
Reference type o' zgaruvchilari heapda saqlanadi. Heapda ma' lumotlar ko'proq joyni talab qiladi, va ular stackdan farqli o'laroq, murakkabroq boshgariladi (masalan, garbage collection orgali).

string concatenation => stringlarni bir biriga qo'shish

var greeting = "Hello" + " " + name + " ";
Console. WriteLine(greeting);

Agar space holder ichida o' zgaruvchidan keyin, 10 soni yoziladigan bo'lsa bizga consoledan 10 ta joy ajratib beradi. Agar -10 yoziladigan bo' lsa chap tarfdan rostlab chop etadi. var butunSon = 2;

Console. WriteLine($"Kiritilgan butunSon: {butunSon,
10: D4}");
Console. WriteLine($"Kiritilgan butunSon: {butunSon, -10:D4}");

string
firstFriend = "Sunnat";
string
secondFriend
= "Firdavs";
Console WriteLine($"The name (firstFriend) and {secondFriend}");

//Length - function tekstni uzinligini aniqlab beradi, o'zgaruvchidan keyin Length shaklida yoziladi.

Console WriteLine($"The name {firstFriend} has {firstFriend.Length) letters");
Console.WriteLine($"The name {secondFriend} has {secondFriend.Length} letters");
var carModel = "BYD Song L";
Console-WriteLine("String = (0}, Length = {1}", carModel, carModel.Length);
for int
1 = 0; 1 < carModel. Length; i++)
Console.WriteLine(carModel [i]) ;

//String metodlari
//TrimStart() - function tekstni oldidagi joylarni olib tashlaydi.
// TrimEnd() - function tekstni oxiridagi joylarni olib tashlaydi
//Trim() - fucntion oldi va oxiridagi joylarni tengdaniga olib tashlaydi.

string greeting2 = "
Hello
Console. WriteLine(greeting2);
string
trimmedGreeting = greeting2. TrimStart();
Console. WriteLine (trimmedGreeting) ;
trimmedGreeting = greeting2.TrimEnd();
Console.WriteLine(trimmedGreeting) ;
trimmedGreeting = greeting2. Trim();
Console. WriteLine(trimmedGreeting);

//Replace() →> function tekst qiymatini o'rniga yangi qiymatga o'zgartirrish imkoniyatini beradi.

string sayHello= "Hello World";
Console.WriteLine(sayHello) ;
sayHello = sayHello.Replace("Hello", "Greetings");
Console.WriteLine(sayHello);

//ToUpper () -> function xamma harflarni kotta qilib beradi. //ToLower () -> fucntion xamma harflarni kichik qilib beradi.

Console.WriteLine(sayHello. ToUpper());
Console.WriteLine(sayHello. ToLower());

//Escape character && verbatim string
// escape character maxsus belgilarni chop etishda backslashda foydalanishimiz kerak - 1

var specialString = "U judayam \"zor\" bola";
Console. WriteLine(specialString);
Console-WriteLine("olma\nanor \nnok");
Console. WriteLine("olma\ tanor\tnok");
Console-WriteLine("olma \banor");
Console-WriteLine("olma\ \anor\ \nok");
Console.WriteLine("C: \ \Windows\ \System32\\calc.exe");
Console-WriteLine(@"C: \Windows\System32\calc.exe");
Console-WriteLine("C: \Windows\nSystem32\ncalc.exe");
Console-WriteLine(@"C: \nWindows\nSystem32\ncalc-exe");

//Contains() - checks whether the string contains a substring

string songLyrics = "You say goodbye, and I say hello";
Console. WriteLine (songLyrics.Contains ("goodbye") );
Console. WriteLine(songLyrics.Contains ("say"));
Console-WriteLine (songLyrics.Contains ("greetings")):
//StartWith() - checks if the string begins with the given string
Console. WriteLine (songLyrics.StartsWith ("You"));
Console WriteLine(songLyrics-StartsWith ("goodbye")) ;
//EndWith() → checks if the string ends with the given string
Console-WriteLine(songLyrics.EndsWith("hello"));