Type

This C# class describes data types—it stores type information in a variable, property or field. The Type class represents the program's metadata (its structure).

For some background, the Type class is found in the System namespace. You can use Type variables in the same way as other variables such as string or int.

Example

Here we see you can assign Type variables to the result of a typeof expression. And methods receive a Type parameter as an argument.

Here A Type is returned by the typeof operator and the GetType method. We call the Test() method and pass the Types to it.

Info The Main method uses Type variables and assigns them to the result of evaluations of the typeof operator.

Tip The Type variables are loaded onto the evaluation stack in the same way as other variables are.

using System;

class Program
{
    static void Main()
    {
        // Use type variables.
        // ... Then pass the variables as an argument.
        Type type1 = typeof(string[]);
        Type type2 = "string".GetType();
        Type type3 = typeof(Type);

        Test(type1);
        Test(type2);
        Test(type3);
    }

    static void Test(Type type)
    {
        // Print some properties of the Type formal parameter.
        Console.WriteLine("IsArray: {0}", type.IsArray);
        Console.WriteLine("Name: {0}", type.Name);
        Console.WriteLine("IsSealed: {0}", type.IsSealed);
        Console.WriteLine("BaseType.Name: {0}", type.BaseType.Name);
        Console.WriteLine();
    }
}IsArray: True
Name: String[]
IsSealed: True
BaseType.Name: Array

IsArray: False
Name: String
IsSealed: True
BaseType.Name: Object

IsArray: False
Name: Type
IsSealed: False
BaseType.Name: MemberInfo

Type notes

In the C# language, the Type class is not used in the inheritance and class-based system. Instead, classes inherit from the Object type.

Type usage

The "Type" type is a representation of the metadata, which is data about the program. It can be thought of as information about the program.

Type objects can be stored as fields and static fields. They can be passed as arguments and used as local variables. Some functions in C# receive Type arguments.