MemberInfo.DeclaringType Property

July 28, 2014

Gets the class that declares this member.

Namespace:  System.Reflection
Assembly:  mscorlib (in mscorlib.dll)

public abstract Type DeclaringType { get; }

Property Value

Type: System.Type
The Type object for the class that declares this member.

The DeclaringType property retrieves a reference to the Type object for the type that declares this member. A member of a type is either declared by the type or inherited from a base type, so the Type object returned by the DeclaringType property might not be the same as the Type object used to obtain the current MemberInfo object.

  • If the Type object from which this MemberInfo object was obtained did not declare this member, the DeclaringType property will represent one of its base types.

  • If the MemberInfo object is a global member (that is, if it was obtained from the Module.GetMethods method, which returns global methods on a module), the returned DeclaringType will be null.

The following example shows how DeclaringType works with classes and interfaces. It uses a helper method named FormatDeclaringType to show how the declaring type of method M changes in classes that implement interfaces or that override and inherit from base classes.

For example, when class B overrides virtual method M from class A, it essentially redefines (or redeclares) this method. Therefore, the MethodInfo for B.M reports the declaring type as B instead of A, although A is where this method was originally declared.

The example also lists the names and declaring types of all the members of class C.


using System;
using System.Reflection;

interface I
{
   string M();
}
// DeclaringType for M is I.

class A: I
{
   public virtual string M()
   {
      return "Implemented in A.";
   }
}
// DeclaringType for M is A.

class B: A
{
   public override string M()
   {
      return "Overridden in B.";
   }
}
// DeclaringType for M is B.

class C: A {}
// DeclaringType for M is A.


class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      outputBlock.Text += FormatDeclaringType(typeof(I), "M");
      outputBlock.Text += FormatDeclaringType(typeof(A), "M");
      outputBlock.Text += FormatDeclaringType(typeof(B), "M");
      outputBlock.Text += FormatDeclaringType(typeof(C), "M");

      // Display the DeclaringType of all public members of C.
      Type t = typeof(C);
      MemberInfo[] members = t.GetMembers();

      outputBlock.Text += String.Format("\nThere are {0} members in {1}:\n",
         members.Length, t.Name);

      foreach(MemberInfo m in members)
      {
         outputBlock.Text += String.Format("The declaring type of {0} is {1}.\n",
            m.Name, m.DeclaringType.FullName);
      }
   }

   private static string FormatDeclaringType(Type t, string m)
   {
      MemberInfo member = t.GetMethod(m);
      return String.Format("The declaring type of {0}, in type {1}, is {2}.\n",
         member.Name, t.Name, member.DeclaringType.Name);
   }
}

/* This example produces the following output:

The declaring type of M, in type I, is I.
The declaring type of M, in type A, is A.
The declaring type of M, in type B, is B.
The declaring type of M, in type C, is A.

There are 6 members in C:
The declaring type of M is A.
The declaring type of ToString is System.Object.
The declaring type of Equals is System.Object.
The declaring type of GetHashCode is System.Object.
The declaring type of GetType is System.Object.
The declaring type of .ctor is C.
 */


Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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