C# – Structs

Structs

Struct is like a class but is a value type and it does not support inheritance. Useful when value-type semantics are desirable. You do not need to define a parameterless constructor but if you do define than you must explictly assign every field.

Struct cannot have:

• Parameterless constructor
• Field initializers
• A finalizer
• Virtual or protected members

public struct Point
{
	public int X, Y;
	public Point (int x, int y) { X = x; Y = y; }
	// The parameterless constructor is implicit.
}

static void Main()
{
	Point p1 = new Point ();       // p1.x and p1.y will be 0
	p1.Dump();
	
	Point p2 = new Point (1, 1);   // p1.x and p1.y will be 1
	p2.Dump();
}

public struct Point
{
	int x = 1;	// Illegal: cannot initialize field
	int y;
	public Point() { }	// Illegal: cannot have parameterless constructor	
	public Point (int x) { this.x = x; }	// Illegal: must assign field y
}

static void Main() { }