Struct vs Class in .Net Framework

Struct vs Class in .Net Framework

 

Posted by: Rickie Lee http://rickie.cnblogs.com

A struct is a user-defined type that is very similar to a class; it can contain constructors, fields, methods, and properties. Structs are declared using the struct keyword instead of class.

 

There are some differences between struct and class in .Net Framework.

1. A struct is a value type, whereas classes are reference types. Internally, structs are implicitly derived from System.ValueType.

The following example shows a simple struct declaration:

public struct Book

{

    public decimal price;

    public string title;

    public string author;

}

 

2. Struct does not support inheritance. A struct can not derive from a class or from another struct. But a class can support inheritance.

 

3. Structs always contain by default a parameterless, default constructor, which does nothing. You’re allowed to add more overloads, but you can’t add a parameterless constructor. That is to say, structs can declare constructors, but they must take parameters.

 

4. Although structs are very powerful, they are mainly designed to act as containers for data rather than as fully featured objects. Because they are value types and are stored on the stack, passing them around can be very fast. While classes are reference types and are stored on the Heap.

 

5. Unlike classes, structs can be instantiated without using a new operator.

 

References:

1. Beginning ASP.NET 2.0 e-commerce in C# 2005 - Apress

2. MSDN