Reflection in C# using the Type Class: Runtime Type Inspection and Manipulation

Explore reflection in C#, a powerful technique for inspecting and manipulating types and their members at runtime. This guide explains the `Type` class, its methods, and how to use reflection for tasks like type checking, invoking methods dynamically, and accessing member information.

Reflection in C# Using the `Type` Class

Reflection in C# is a powerful feature that allows you to inspect and manipulate types and their members (methods, properties, fields, etc.) at runtime. The `Type` class is central to this process, providing methods and properties to access type information dynamically.

Understanding Reflection

Reflection is the ability of a program to examine its own structure and behavior while it's running. It's like having a mirror that shows you the internal workings of your code. This is useful for a variety of tasks, including:

  • Dynamically creating and working with objects.
  • Inspecting the members of a class.
  • Invoking methods.
  • Building flexible and extensible applications.

The `Type` Class

The `Type` class (in the `System` namespace) represents a type in the Common Type System (CTS). You can obtain a `Type` object using `typeof(MyClass)` or `myObject.GetType()`. The `Type` object provides methods to access its members and properties.

Key Properties of the `Type` Class

Property Description
Assembly Gets the assembly containing the type.
AssemblyQualifiedName Gets the fully qualified name, including assembly information.
Attributes Gets attributes applied to the type.
BaseType Gets the base type (if any).
FullName Gets the fully qualified name of the type.
IsAbstract, IsArray, IsClass, IsEnum, IsInterface, IsNested, IsPrimitive, IsPointer, IsNotPublic, IsPublic, IsSealed, IsSerializable Boolean properties indicating type characteristics.
MemberType Indicates the member type (if nested).
Module Gets the module containing the type.
Name Gets the simple name of the type.
Namespace Gets the namespace of the type.

Key Methods of the `Type` Class

Method Description
GetConstructors(), GetConstructors(BindingFlags) Retrieves constructor information.
GetFields(), GetFields(BindingFlags) Retrieves field information.
GetMembers(), GetMembers(BindingFlags) Retrieves all members (methods, fields, properties, etc.).
GetMethods(), GetMethods(BindingFlags) Retrieves method information.
GetProperties(), GetProperties(BindingFlags) Retrieves property information.
GetType() Gets the type of the current instance.
GetType(string typeName) Gets the type with the specified name.

Examples

Example 1: Getting Type Information


Type myType = typeof(int);
Console.WriteLine(myType); //Output: System.Int32

Example 2: Getting Assembly Information


Type myType = typeof(string);
Console.WriteLine(myType.Assembly); // Output: mscorlib

Example 3: Printing Type Details


Type myType = typeof(string);
Console.WriteLine(myType.FullName);
Console.WriteLine(myType.BaseType);
Console.WriteLine(myType.IsClass);

Example 4: Getting Constructors


Type myType = typeof(string);
ConstructorInfo[] constructors = myType.GetConstructors();
foreach (ConstructorInfo constructor in constructors) {
    Console.WriteLine(constructor);
}

Example 5: Getting Methods


Type myType = typeof(string);
MethodInfo[] methods = myType.GetMethods();
foreach (MethodInfo method in methods) {
    Console.WriteLine(method);
}

Example 6: Getting Fields


Type myType = typeof(string);
FieldInfo[] fields = myType.GetFields(BindingFlags.Public | BindingFlags.Static | BindingFlags.NonPublic);
foreach (FieldInfo field in fields) {
    Console.WriteLine(field);
}