Structs

A struct (or structure) is a value type which encapsulates a small group of related variables.

Structs prove efficient in certain situations; for example, an application requiring a declaration of an array with 2,000 objects of the same type allocates too much memory. They represent a record; for example, a laser cutter with a model name, model number, type, and product ID number. Structs can hold constructors, fields, constants, methods, indexers, events, properties, operators, and nested types; however, if several members are necessary, a class would be more appropriate. Review struct syntax below:

public struct Pizza
{
	public float price;
	public string name;
	public string size;
}

Review the example below to see the struct in use:

using System;
struct Pizza
{
	private float price;
	private string name;
	private string size;
	private int productID;
	public void getInfo(string n, string s, float p, int pi)
	{
		price = p;
		name = n;
		size = s;
		productID = pi;
	}
	public void show()
	{
		Console.WriteLine(name + ”{0}” + size + “{0}” + “$” + price);
	}
}
public class PizzaTest
{
	public static void Main(string[] args)
	{
		Pizza Pizza1 = new Pizza();
		Pizza Pizza2 = new Pizza();
		Pizza1.getInfo("The Californian",”Medium”, "15.00");
		Pizza2.getInfo("Soul Food","Medium", "25.00");
		Pizza1.show();
		Pizza2.show();
		Console.ReadKey();
	}
}

Structs have the following limitations:

1. Though they can implement interfaces, structs cannot inherit; thus, they cannot have protected members.
2. Defining a default (no parameters) constructor for a struct causes an error.
3. Initializing an instance field within a struct body causes an error.