Programming in the .NET Environment

The C# Type System

Reference Versus Value Types

The type system of the Common Language Runtime is divided into two worlds. Reference types are heap-allocated types and are used for most objects. Value types are either stack-allocated or allocated as part of another object; they are used for the predefined numeric types and other types that “feel like data.”

This two-type system presents a problem for languages such as C#, which wish to present a unified type system where possible. If reference types and value types remained in separate worlds, it wouldn't be possible to write something like the following:

int value = 55; 
double precision = 0.35;
Console.WriteLine("Result: {0}, {1}", value, precision);

For this code to work would require an ...