Forem: firdavs090

C# {DateTime}

firdavs090 — Wed, 31 Jul 2024 11:13:03 +0000

Current Date and Time:

Now: Gets the current date and time.

DateTime now = DateTime.Now;

UtcNow: Gets the current date and time in Coordinated Universal Time (UTC).

DateTime utcNow = DateTime.UtcNow;

Specific Date and Time:

Constructor: Creates a specific date and time.

DateTime specificDate = new DateTime(2024, 7, 31, 14, 30, 0);

Today: Gets the current date with the time component set to 00:00:00.

DateTime today = DateTime.Today;

Parsing:

Parse: Converts the string representation of a date and time to its 'DateTime' equivalent.

DateTime parsedDate = DateTime.Parse("2024-07-31");

TryParse: Tries to convert the string representation of a date and time to its 'DateTime' equivalent and returns a boolean indicating success or failure.

DateTime result;
bool success = DateTime.TryParse("2024-07-31", out result);

DateTime Properties:

Year, Month, Day: Gets the year, month, and day components of the date.

int year = now.Year;
int month = now.Month;
int day = now.Day;

Hour, Minute, Second: Gets the hour, minute, and second components of the time.

int hour = now.Hour;
int minute = now.Minute;
int second = now.Second;

DayOfWeek: Gets the day of the week.

DayOfWeek dayOfWeek = now.DayOfWeek;

DayOfYear: Gets the day of the year.

int dayOfYear = now.DayOfYear;

DateTime Methods:
Adding and Subtracting:

AddDays, AddMonths, AddYears: Adds the specified number of days, months, or years to the date.

DateTime nextWeek = now.AddDays(7);
DateTime nextMonth = now.AddMonths(1);
DateTime nextYear = now.AddYears(1);

AddHours, AddMinutes, AddSeconds: Adds the specified number of hours, minutes, or seconds to the time.

DateTime inTwoHours = now.AddHours(2);
DateTime inThirtyMinutes = now.AddMinutes(30);
DateTime inTenSeconds = now.AddSeconds(10);

Subtract:

Subtract: Subtracts a specified time interval from the date.

TimeSpan duration = new TimeSpan(1, 0, 0, 0); // 1 day
DateTime yesterday = now.Subtract(duration);

Comparison:

CompareTo: Compares two DateTime instances.

int comparison = now.CompareTo(specificDate);

Equals: Checks if two DateTime instances are equal.

bool isEqual = now.Equals(specificDate);

Before, After: Checks if one date is before or after another date.

bool isBefore = specificDate < now;
bool isAfter = specificDate > now;

Formatting DateTime:

ToString: Converts the DateTime to its string representation.

string dateString = now.ToString();

ToString with format: Converts the DateTime to its string representation with a specified format.

string formattedDate = now.ToString("yyyy-MM-dd HH:mm:ss");

C# {String Methods}

firdavs090 — Wed, 31 Jul 2024 10:49:16 +0000

Length:

1)Length: Gets the number of characters in the string.

string str = "Hello, World!";
int length = str.Length; // 13

Accessing Characters:

1)indexer: Gets the character at a specified index.

char ch = str[0]; // 'H';

Comparison:

1)Equals: Compares two strings for equality.

bool isEqual = str.Equals("Hello, World!"); // true

CompareTo:
1)Compares two strings lexicographically.

int comparison = str.CompareTo("Hello"); // > 0

Compare:
1)Compares two strings with optional culture, case, and sort rules.

int comparison = string.Compare(str, "Hello"); // > 0

Searching:

Contains: Determines whether a substring occurs within the string.

bool contains = str.Contains("World"); // true

StartsWith: Determines whether the string starts with a specified substring.

bool startsWith = str.StartsWith("Hello"); // true

EndsWith: Determines whether the string ends with a specified substring.

bool endsWith = str.EndsWith("World!"); // true

IndexOf: Returns the index of the first occurrence of a specified substring.

int index = str.IndexOf("World"); // 7

LastIndexOf: Returns the index of the last occurrence of a specified substring.

int lastIndex = str.LastIndexOf("o"); // 8

Modification:

Substring: Extracts a substring from the string.

string sub = str.Substring(7, 5); // "World"

Replace: Replaces all occurrences of a specified substring with another substring.

string replaced = str.Replace("World", "C#"); // "Hello, C#!"

Remove: Removes a specified number of characters from the string.

string removed = str.Remove(5, 7); // "Hello!"

Insert: Inserts a specified substring at a specified index.

string inserted = str.Insert(7, "beautiful "); // "Hello, beautiful World!"

Case Conversion:

ToUpper: Converts the string to uppercase.

string upper = str.ToUpper(); // "HELLO, WORLD!"

ToLower: Converts the string to lowercase.

string lower = str.ToLower(); // "hello, world!"

Trimming:

Trim: Removes all leading and trailing white-space characters from the string.

string trimmed = str.Trim();

TrimStart: Removes all leading white-space characters from the string.

string trimmedStart = str.TrimStart();

TrimEnd: Removes all trailing white-space characters from the string.

string trimmedEnd = str.TrimEnd();

Splitting and Joining:

Split: Splits the string into an array of substrings based on a specified delimiter.

string[] words = str.Split(' '); // {"Hello,", "World!"}

Join: Concatenates an array of strings into a single string, with an optional separator.

string joined = string.Join(" ", words); // "Hello, World!"

Format:

Format: Replaces the format items in a string with the string representation of specified objects.

string formatted = string.Format("Welcome, {0}!", "John"); // "Welcome, John!"

C# {Data Types except Int}

firdavs090 — Wed, 31 Jul 2024 10:16:21 +0000

Floating-Point Types:

1)float: 32-bit single-precision floating point type
2)double: 64-bit double-precision floating point type

float myFloat = 20.5f;

Decimal Type:

1)decimal: 128-bit precise decimal values with 28-29 significant digits, suitable for financial and monetary calculations

decimal myDecimal = 100.5m;

Other Value Types:

1)char: 16-bit Unicode character
2)bool: Represents Boolean values, true or false

bool myBool = true;
char myChar = 'A';

Reference Types:
String Type:

1)string: Represents a sequence of Unicode characters

string myString = "Hello, World!";

Object Type:

1)object: The base type from which all other types derive

object myObject = myString;

Dynamic Type

1)dynamic: Type resolved at runtime, providing flexibility at the cost of some performance and type safety

dynamic myDynamic = 10; // dynamic type can change

Nullable Types

1)Nullable: Allows value types to be assigned null (e.g., int?, double?)

int? myNullableInt = null;

Arrays:

1)Array: Represents a fixed-size sequence of elements of the same type

int[] myArray = {1, 2, 3, 4, 5};

Enum Type:

1)enum: Represents a set of named constants

enum Day { Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday }
Day today = Day.Monday;

Struct Type:

1)struct: A value type that can encapsulate data and related functionality

struct Point 
{
    public int X;
    public int Y;
}
Point p = new Point();
p.X = 10;
p.Y = 20;

Class Type:

1)class: A reference type that can encapsulate data and related functionality

class MyClass {
    public int Number;
    public void Display() {
        Console.WriteLine(Number);
    }
}
MyClass obj = new MyClass();
obj.Number = 5;
obj.Display();

Interface Type:

1)interface: Defines a contract that can be implemented by classes and structs

class MyClassWithInterface : IMyInterface 
{
    public void MyMethod() 
{
        Console.WriteLine("Interface Method");
    }
}
IMyInterface myInterface = new MyClassWithInterface();
myInterface.MyMethod();

Delegate Type:

1)delegate: Represents a reference to a method

delegate void MyDelegate(string message);
MyDelegate del = (msg) => Console.WriteLine(msg);
del("Hello, Delegate!");

C# {Integral Types}

firdavs090 — Wed, 31 Jul 2024 09:58:15 +0000

Integral Types:

1)byte: 8-bit unsigned integer (0 to 255)
2)sbyte: 8-bit signed integer (-128 to 127)
3)short: 16-bit signed integer (-32,768 to 32,767)
4)ushort: 16-bit unsigned integer (0 to 65,535)
5)int: 32-bit signed integer (-2,147,483,648 to 2,147,483,647)
6)uint: 32-bit unsigned integer (0 to 4,294,967,295)
7)long: 64-bit signed integer (-9,223,372,036,

using System;

class Program
{
    static void Main()
    {
        // byte: 8-bit unsigned integer (0 to 255)
        byte myByte = 255;
        Console.WriteLine("byte: " + myByte);

        // sbyte: 8-bit signed integer (-128 to 127)
        sbyte mySByte = -128;
        Console.WriteLine("sbyte: " + mySByte);

        // short: 16-bit signed integer (-32,768 to 32,767)
        short myShort = -32768;
        Console.WriteLine("short: " + myShort);

        // ushort: 16-bit unsigned integer (0 to 65,535)
        ushort myUShort = 65535;
        Console.WriteLine("ushort: " + myUShort);

        // int: 32-bit signed integer (-2,147,483,648 to 2,147,483,647)
        int myInt = -2147483648;
        Console.WriteLine("int: " + myInt);

        // uint: 32-bit unsigned integer (0 to 4,294,967,295)
        uint myUInt = 4294967295;
        Console.WriteLine("uint: " + myUInt);

        // long: 64-bit signed integer (-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807)
        long myLong = -9223372036854775808;
        Console.WriteLine("long: " + myLong);

        // ulong: 64-bit unsigned integer (0 to 18,446,744,073,709,551,615)
        ulong myULong = 18446744073709551615;
        Console.WriteLine("ulong: " + myULong);
    }

{IL} --> {Intermediate Language}

firdavs090 — Tue, 02 Jul 2024 11:49:42 +0000

IL (Intermediate Language) .NET’dagi oraliq til boʻlib, MSIL (Microsoft Intermediate Language) yoki CIL (Common Intermediate Language) nomi bilan ham tanilgan. C# yoki VB.NET kabi tillardagi manba kodi to'g'ridan-to'g'ri mashina kodiga emas, balki birinchi navbatda ILga kompilyatsiya qilinadi va bu uni platformadan mustaqil qiladi.

Arxitektura mustaqilligi: IL kodi CLR (Common Language Runtime) ning tegishli versiyasi o'rnatilgan har qanday platformada ishlashi mumkin. Bu ishlab chiquvchilarga kodni bir marta yozish va uni turli xil operatsion tizimlar va protsessor arxitekturalarida ishga tushirish imkonini beradi.

JIT kompilyatsiyasi: Dastur ishga tushirilganda, IL JIT kompilyatori (Just-In-Time kompilyatori) yordamida mashina kodiga aylantiriladi. Ushbu jarayon maqsadli platformada optimal ishlashni ta'minlash uchun ish vaqtida sodir bo'ladi.

Turning xavfsizligi va modulliligi: IL CLR tomonidan turdagi xavfsizligini tekshirish va kod yaxlitligini ta'minlash uchun ishlatiladigan metama'lumotlarni o'z ichiga oladi. Modullashtirishni qo'llab-quvvatlash ilovani ish vaqtida birga yig'iladigan alohida komponentlarga bo'lish imkonini beradi.

Tilning mosligi: Barcha .NET tillari IL-ga kompilyatsiya qilinganligi sababli ular bir-biri bilan osongina o'zaro ishlashi mumkin. Bu shuni anglatadiki, siz bir xil dasturning turli qismlarini moslik muammosisiz ishlab chiqish uchun turli dasturlash tillaridan foydalanishingiz mumkin.

IL kodning koʻchishi va xavfsizligini taʼminlaydi, turli .NET tillari oʻrtasida oʻzaro ishlashni soddalashtiradi va ishlab chiquvchilarga koʻp qirrali va xavfsiz ilovalar yozish imkonini beradi.

{CLR}

firdavs090 — Tue, 02 Jul 2024 11:23:47 +0000

Asosiy xususiyatlar: CLR .NET platformasida yozilgan boshqariladigan ilovalar uchun ish vaqti muhitini taqdim etadi. U kodning bajarilishini boshqaradi, kod xavfsizligini, xotirani boshqarishni va dastur bajarilishining boshqa jihatlarini ta'minlaydi.

Xotirani boshqarish: CLR avtomatik xotira boshqaruvidan foydalanadi, bu esa ishlab chiquvchilarning xotirani aniq ajratish va ajratish zaruratini yo'q qiladi.

Mavzuni boshqarish: CLR bajarilish iplarini boshqarish, shu jumladan umumiy ma'lumotlarga kirishni sinxronlashtirish uchun imkoniyatlarni taqdim etadi.

Tur xavfsizligi: CLR ma'lumotlar turlaridan noto'g'ri foydalanish bilan bog'liq ko'plab ish vaqtidagi xatolarning oldini olishga yordam beradigan tip xavfsizligini ta'minlaydi.

Bir nechta tilni qo'llab-quvvatlash: CLR O'rta til (IL) ga kompilyatsiya qilingan bir nechta dasturlash tillarini qo'llab-quvvatlaydi, bu ishlab chiquvchilarga bir xil dastur yoki loyiha doirasida bir nechta tillardan foydalanishga imkon beradi.

.NET Framework bilan integratsiya: CLR .NET Frameworkning asosiy qismi boʻlib, .NET tarkibiga kiritilgan turli tillarda yozilgan komponentlarning oʻzaro ishlashini taʼminlaydi.

CLR apparat va operatsion tizimdan yuqori darajadagi abstraktsiyani ta'minlash orqali .NET ilovalarini ishlab chiqishni sezilarli darajada soddalashtiradi, bu esa ishlab chiquvchilarga resurs va platformalarni boshqarish tafsilotlariga emas, balki dastur mantig'iga e'tibor qaratishga imkon beradi.

{SDK vs Runtime}

firdavs090 — Tue, 02 Jul 2024 08:30:26 +0000

SDK (Dasturiy ta'minotni ishlab chiqish to'plami):

SDK - bu .NET platformasida ilovalarni ishlab chiqish uchun mo'ljallangan asboblar va kutubxonalar to'plami. Bunga quyidagilar kiradi:

Kompilyatorlar: C#, F# yoki VB.NET dasturlash tillarida manba kodini bajariladigan kodga aylantirish uchun.
Kutubxonalar va dasturchilar asboblari: Har xil turdagi ilovalarni (masalan, veb-ilovalar, ish stoli ilovalari) ishlab chiqish uchun zarur bo'lgan sinf kutubxonalari to'plami (masalan, asosiy sinf kutubxonasi - BCL).
Hujjatlar va kod misollari: Ishlab chiquvchilarga ilovalarni yaratish, sinab ko'rish va disk raskadrovka qilishda yordam beradigan manbalar.

Runtime (CLR - Common Language Runtime)

CLR (Common Language Runtime) .NET dasturlarini ishga tushiradigan ish vaqti muhitidir. U quyidagilarni ta'minlaydi:

Xotirani boshqarish va axlat yig'ish: Avtomatik xotirani boshqarish, foydalanilmagan resurslarni bo'shatish va axlat yig'ish.
Istisnolarni boshqarish: istisnolarni boshqarish va dasturni bajarish paytida xatolarni qayta ishlash.
Ko'p ish zarralarini qo'llab-quvvatlash: bir nechta dastur iplari bilan ishlash mexanizmlari.

SDK va Runtime o'rtasidagi o'zaro ta'sir:

SDK dasturchi tomonidan ilovalarni yozish va yaratish uchun ishlatiladi. U ilovalar yaratish uchun zarur bo'lgan vositalar va kutubxonalarni taqdim etadi.
Ish vaqti dasturni bajarish jarayonida uni bajarish uchun ishlatiladi. U kerakli ijro muhitini ta'minlaydi va ilovaning bajarilishi jarayonini boshqaradi.

Shunday qilib, SDK va Runtime .NET ilovalarini ishlab chiqish va ishga tushirish uchun birgalikda ishlaydi, ishlab chiquvchilarni .NET platformasida dasturiy ta'minotni yaratish va muvaffaqiyatli ishga tushirish uchun barcha zarur vositalar va muhit bilan ta'minlaydi.

Dotnet's versions.

firdavs090 — Tue, 02 Jul 2024 07:42:17 +0000

.NET Framework:

1.0: ASP.NET, ADO.NET va Windows Forms bilan birinchi versiya.
1.1: Mobil rivojlanishni qo'llab-quvvatlash, xavfsizlikni yaxshilash.
2.0: Jeneriklarni joriy etish, yangi boshqaruv elementlari, 64-bitli tizimlarni qo'llab-quvvatlash.
3.0: WPF (Windows Presentation Foundation), WCF (Windows Communication Foundation), WF (Windows Workflow Foundation), CardSpace.
3.5: LINQ, ASP.NET AJAX ga kirish.
4.0: Parallel dasturlashni takomillashtirish, Boshqariladigan Kengaytirish Framework (MEF).
4.5: Asinxron va kutish bilan asinxron dasturlash.

.NET Core:

1.0: Birinchi kross-platforma versiyasi, Windows, macOS va Linuxni qo'llab-quvvatlaydi.
2.0: Yaxshilangan ishlash, ko'proq API.
2.1 va 2.2: Qo'shimcha ish faoliyatini yaxshilash va yangi API'lar.
3.0 va 3.1: Windows Forms va WPF-ni qo'llab-quvvatlash, ish stoli ilovalari uchun yaxshilanishlar.

.NET birlashtirish:

.NET 5.0: .NET Framework va .NET Core-ni yaxshilangan ishlash va xavfsizlik bilan yagona platformaga birlashtirish.
.NET 6.0: Uzoq muddatli qo'llab-quvvatlash (LTS), yangi xususiyatlar va ish faoliyatini yaxshilash.
.NET 7.0: Ishlash va unumdorlikni yanada yaxshilash.
.NET 8.0: Keyingi yaxshilanishlar va yangiliklar e'lon qilindi.

Asosiy komponentlar:

CLR (Common Language Runtime): .NET dasturlarini ishga tushiradi.
BCL (Base Class Library): Turli vazifalar uchun umumiy kodlar kutubxonasi.
ASP.NET: Veb-ilovalarni yaratish uchun asos.
ADO.NET: Ma'lumotlarga kirish uchun sinflar.
Windows shakllari va WPF: ish stoli ilovalari uchun kutubxonalar.
Xamarin: Mobil ilovalar uchun ramka.
Blazor: C# yordamida veb-interfeyslarni yaratish uchun ramka.

Dotnet's hisotry.

firdavs090 — Tue, 02 Jul 2024 07:13:42 +0000

.NET (toʻliq nomi Microsoft .NET Framework) — Microsoft tomonidan turli turdagi ilovalarni yaratish va joylashtirishni soddalashtirish uchun ishlab chiqilgan platforma. U 2000-yillarning boshida turli texnologiyalar va vositalarni yagona ishlab chiqish platformasida birlashtirgan Windows xizmatlarining keyingi avlodi sifatida taqdim etilgan.

.NET ning chiqarilishi bilan veb-ishlab chiqish uchun ASP.NET va ish stoli ilovalarini yaratish uchun Windows Forms kabi asosiy komponentlar taqdim etildi. Platforma doimiy ravishda rivojlanib bordi, yangi xususiyatlar qo'shdi va ish faoliyatini yaxshilaydi.

So'ngi yillarda Microsoft ochiq manbali .NET va .NET Core-ni taqdim etdi, bu esa ishlab chiquvchilarga nafaqat Windows, balki macOS va Linuxda ham ishlaydigan ilovalar yaratish imkonini berdi. Bu harakat .NET ni yanada qulayroq va moslashuvchan platformaga aylantirdi.

.NET Framework va .NET Core-ni yagona platformaga birlashtirib, .NET ishlab chiquvchilar uchun yaxshilangan ishlash, xavfsizlik va mahsuldorlikni ta'minlaydi. Zamonaviy .NET platformasi zamonaviy ilovalarni yaratish uchun keng ko'lamli texnologiyalar va arxitekturalarni qo'llab-quvvatlaydi.

While Loop c++

firdavs090 — Wed, 06 Mar 2024 10:08:45 +0000

Цикл 'while' в C++ является предварительным тестовым циклом, что означает, что он проверяет условие перед выполнением блока кода внутри него. Вот базовый синтаксис цикла 'whlie':
while (условие) { // Блок кода, который будет выполняться повторно }
Цикл начинается с ключевого слова while, за которым следует условие в круглых скобках. Если условие оценивается как истинное, выполняется блок кода внутри цикла. После каждой итерации условие оценивается снова. Цикл продолжается, пока условие не станет ложным.
Простой пример:
`int son,i = 1;

cin >> son;

while(i <= son)
{
cout << "Hello world" << endl;
i++;
}`