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A delegate is a type that represents references to methods with a particular parameter list and return type. When we instantiate a delegate, we can associate its instance with any method with a compatible signature and return type. We can invoke (or call) the method through the delegate instance.Func DelegateFunc is a generic delegate included in the System namespace. It has zero or more input parameters and one out parameter. The last parameter is considered as an out parameter. This delegate can point to a method that takes up to 16 Parameters and returns a value.Below is the Func delegate ... Read More
A string having number can be validated using int.TryParse or int.Parse.Int.Parse throws an exception if it cannot parse the string to an integer, whereas Int.TryParse returns a bool indicating whether it succeeded. Also, Int.TryParse has an out parameter which has the value of the parsed string.Example Live Demousing System; namespace DemoApplication { class Program { static void Main(string[] args) { string numberString = "123"; int number = 0; if(int.TryParse(numberString, out number)) { Console.WriteLine($"Try Parse Interger Number: {number}"); ... Read More
For creating a directory, we must first import the System.IO namespace in C#. The namespace is a library that allows you to access static methods for creating, copying, moving, and deleting directories.It is always recommended to check if the Directory exist before doing any file operation in C# because the complier will throw exception if the folder does not exist.Exampleusing System; using System.IO; namespace DemoApplication { class Program { static void Main(string[] args) { string folderName = @"D:\Demo Folder"; // If directory does not exist, create it ... Read More
Convert the dateTime to toString that results in converting the DateTime to “YYYYMMDDHHMMSS” formatThere are also other formats that the dateTime can be convertedMM/dd/yyyy 08/22/2020dddd, dd MMMM yyyy Tuesday, 22 August 2020dddd, dd MMMM yyyy HH:mm Tuesday, 22 August 2020 06:30dddd, dd MMMM yyyy hh:mm tt Tuesday, 22 August 2020 06:30 AMdddd, dd MMMM yyyy H:mm Tuesday, 22 August 2020 6:30dddd, dd MMMM yyyy h:mm tt Tuesday, 22 August 2020 6:30 AMdddd, dd MMMM yyyy HH:mm:ss Tuesday, 22 August 2020 06:30:07MM/dd/yyyy HH:mm 08/22/2020 06:30MM/dd/yyyy hh:mm tt 08/22/2020 06:30 AMMM/dd/yyyy H:mm 08/22/2020 6:30MM/dd/yyyy h:mm tt 08/22/2020 6:30 AMMM/dd/yyyy HH:mm:ss 08/22/2020 06:30:07Example Live ... Read More
A power of 2 is a number of the form 2n where n is an integerThe result of exponentiation with number two as the base and integer n as the exponent.n2n01122438416532Example 1 Live Democlass Program { static void Main() { Console.WriteLine(IsPowerOfTwo(9223372036854775809)); Console.WriteLine(IsPowerOfTwo(4)); Console.ReadLine(); } static bool IsPowerOfTwo(ulong x) { return x > 0 && (x & (x - 1)) == 0; } }OutputFalse TrueExample 2 Live Democlass Program { static void Main() { Console.WriteLine(IsPowerOfTwo(9223372036854775809)); Console.WriteLine(IsPowerOfTwo(4)); Console.ReadLine(); } static bool IsPowerOfTwo(ulong n) { if (n == 0) return false; while (n != 1) { if (n % 2 != 0) return false; n = n / 2; } return true; } }OutputFalse True
Deep copies duplicate everything. A deep copy of a collection is two collections with all of the elements in the original collection duplicatedDeep Copy is used to make a complete deep copy of the internal reference types.In another words a deep copy occurs when an object is copied along with the objects to which it refersExample Live Democlass DeepCopy { public int a = 10; } class Program { static void Main() { //Deep Copy DeepCopy d = new DeepCopy(); d.a = 10; DeepCopy d1 = new ... Read More
The Enum Flags is used to take an enumeration variable and allow it hold multiple values. It should be used whenever the enum represents a collection of flags, rather than representing a single valueUse the FlagsAttribute for an enumeration only if a bitwise operation (AND, OR, EXCLUSIVE OR) is to be performed on a numeric value.Define enumeration constants in powers of two, that is, 1, 2, 4, 8, and so on. This means the individual flags in combined enumeration constants do not overlap.Example Live Democlass Program { [Flags] enum SocialMediaFlags { None = 0, Facebook = 1, Twitter = ... Read More
Typeof()The type takes the Type and returns the Type of the argument.GetType()The GetType() method of array class in C# gets the Type of the current instance.isThe "is" keyword is used to check if an object can be casted to a specific type. The return type of the operation is Boolean.Example Live Democlass Demo { } class Program { static void Main() { var demo = new Demo(); Console.WriteLine($"typeof { typeof(Demo)}"); Type tp = demo.GetType(); Console.WriteLine($"GetType {tp}"); if (demo is Demo) { ... Read More
Singleton Pattern belongs to Creational type patternSingleton design pattern is used when we need to ensure that only one object of a particular class is Instantiated. That single instance created is responsible to coordinate actions across the application.As part of the Implementation guidelines we need to ensure that only one instance of the class exists by declaring all constructors of the class to be private. Also, to control the singleton access we need to provide a static property that returns a single instance of the object.ExampleSealed ensures the class being inherited and object instantiation is restricted in the derived classPrivate ... Read More
StaticStatic is a keywordStatic classes can contain only static membersStatic objects are stored in stack.Static cannot implement interfaces, inherit from other classesSingletonSingleton is a design patternSingleton is an object creational pattern with one instance of the classSingleton can implement interfaces, inherit from other classes and it aligns with the OOPS conceptsSingleton object can be passed as a referenceSingleton supports object disposalSingleton object is stored on heapSingleton objects can be clonedSingleton objects are stored in Heap