C# Struct

Struct type is value type which inherits from object type and struct keyword is used to define the Struct type in C#.

Define the Struct :

Here is an example of srtuct type – Point which has two properties X & Y co-ordinate

       struct point

        {

            public int x;

            public int y;

        }

Define a constructor of Struct:

We can define the constructor of Struct type to initialize the struct type’s variables

struct point

        {

            public int x;

            public int y;

            public point(int _x , int _y)

            {

                x = _x;

                y = _y;

            }

        }

a struct cannot declare a parameterless constructor .

Define a method of Struct:

We can define a method or function in struct type and there are two Distance () methods to calculate distance between two given points

     struct point

        {

            public int x;

            public int y;

            public point(int _x , int _y)

            {

                x = _x;

                y = _y;

            }

            public double Distance(point p1, point p2)

            {

                return Math.Sqrt(((p1.x - p2.x) * (p1.x - p2.x)) + ((p1.y - p2.y) * (p1.y - p2.y)));

            }

            public double Distance(point p1)

            {

                return Math.Sqrt(((this.x - p1.x) * (this.x - p1.x)) + ((this.y - p1.y) * (this.y - p1.y)));

            }

        }

Instantiate the object of Struct:

new keyword is used to instantiate the object of struct and it calls constructor to set the initial value of struct

point p1 = new point(1,2)

But without new keyword, we can create instance of struct with default value.

point p1;

both struct properties p1.x and p1.y have default unassigned value

Instantiate the Array of Struct type:

Here is an examples of array of struct type

point [] Points = new point[] { new point(2, 3), new point(12, 30 ), new point(40, 50 ) };

Difference between Structs and Classes:

Struct	Class
Struct cannot inherit another struct	Classes can inherit from another class
Struct cannot  be de-initialized	Classes can be de-initialized,
Struct is value type	Class is reference type
Struct cannot have parameterless constructor	Class can have parameterless constructor