Aggregation is a directional relation between objects in C#. It is the relationship between objects.For example, Employee and AddressAn Employee is associated with a single Department, whereas a Department can have more than one employee. Let us see an example of Employee and Address −public class Address {    . . . } public class Employee {    private Address addr;    public Employee (Address addr) {       this.addr = addr;    }    . . . }

Like any other programming language, in C#, you can easily create a user-defined exception. User-defined exception classes are derived from the Exception class. Custom exceptions are what we call user-defined exceptions.In the below example, the exception created is not a built-in exception; it is a custom exception −TempIsZeroExceptionYou can try to run the following code to learn how to create a user-defined exception in C# −Example Live Demousing System; namespace Demo {    class TestTemperature {       static void Main(string[] args) {          Temperature temp = new Temperature();          try {   ... Read More

The User defined data types in C# are structures and enumeration.StructureIn C#, a structure is a value type data type. It helps you to make a single variable hold related data of various data types. The struct keyword is used for creating a structure.The C# structures have the following features −Structures can have methods, fields, indexers, properties, operator methods, and events.Structures can have defined constructors, but not destructors. However, you cannot define a default constructor for a structure. The default constructor is automatically defined and cannot be changed.Unlike classes, structures cannot inherit other structures or classes.Structures cannot be used as ... Read More

The following are the unary operators in C# −+ - ! ~ ++ -- (type)* & sizeofLet us learn about the sizeof operator. The sizeof returns the size of a data type.Let’s say you need to find the size of int datatype −sizeof(int)For double datatype −sizeof(double)Let us see the complete example to find the size of various datatypes −Example Live Demousing System; namespace Demo {    class Program {       static void Main(string[] args) {          Console.WriteLine("The size of int is {0}", sizeof(int));          Console.WriteLine("The size of int is ... Read More

The mechanism of linking a function with an object during compile time is called early binding. It is also called static binding. C# provides two techniques to implement static polymorphism i.e Function overloading and Operator overloading.Let us learn about Function Overloading with an example −You can have multiple definitions for the same function name in the same scope. The definition of the function must differ from each other by the types and/or the number of arguments in the argument list. You cannot overload function declarations that differ only by return type.The following is the complete example −Example Live Demousing System; ... Read More

In Dynamic binding, the compiler will not do type checking at compile time. At runtime, the checking is done.Use it to avoid the restriction of anonymous types to one method. This is only because the type name is visible only to the compiler; therefore, you cannot declare it as the return value of a method.Let us see an example −public dynamic GetAnonymousType() {    return new {       StudentName = "Jack",       Subject = "Maths",    }; }Above, the method is set to be dynamic, that would mean the compiler won’t do type checking at compile time −public dynamic GetAnonymousType() {}

Under Composition, if the parent object is deleted, then the child object also loses its status. The composition is a special type of Aggregation and gives a part-of relationship.For example, A Car has an engine. If the car is destroyed, the engine is destroyed as well.public class Engine {    . . . } public class Car {    Engine eng = new Engine();    ....... }Aggregation is a directional relation between objects in C#. It is the relationship between objects.For example, Employee and AddressAn Employee is associated with a single Department, whereas a Department can have more than one employee. Let ... Read More

Structure In C#, a structure is a value type data type. It helps you to make a single variable hold related data of various data types. The struct keyword is used for creating a structure. To define a structure, you must use the struct statement. The struct statement defines a new data type, with more than one member for your program. Classes When you define a class, you define a blueprint for a data type. A class definition starts with the keyword class followed by the class name, and the class body enclosed by a pair of curly braces. Structure ... Read More

When you define a class, you define a blueprint for a data type.Objects are instances of a class. The methods and variables that constitute a class are called members of the class.To access the class members, you use the dot (.) operator after the object name. The dot operator links the name of an object with the name of a member for example, Box Box1 = new Box();Above you can see Box1 is our object. We will use it to access the members −Box1.height = 7.0;You can also use it to call member functions −Box1.getVolume();The following is an example showing ... Read More

Runtime polymorphism has method overriding that is also known as dynamic binding or late binding. It is implemented by abstract classes and virtual functions.Abstract ClassesAbstract classes contain abstract methods, which are implemented by the derived class.Let us see an example of abstract classes that implements run time polymorphism −Example Live Demousing System; namespace PolymorphismApplication {    abstract class Shape {       public abstract int area();    }    class Rectangle: Shape {       private int length;       private int width;       public Rectangle( int a = 0, int b = 0) {     ... Read More