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CA1410: COM registration methods should be matched


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The latest version of this topic can be found at CA1410: COM registration methods should be matched.

|Breaking Change|Non-breaking|

A type declares a method that is marked with the System.Runtime.InteropServices.ComRegisterFunctionAttribute attribute but does not declare a method that is marked with the System.Runtime.InteropServices.ComUnregisterFunctionAttribute attribute, or vice versa.

For Component Object Model (COM) clients to create a .NET Framework type, the type must first be registered. If it is available, a method that is marked with the ComRegisterFunctionAttribute attribute is called during the registration process to run user-specified code. A corresponding method that is marked with the ComUnregisterFunctionAttribute attribute is called during the unregistration process to reverse the operations of the registration method.

To fix a violation of this rule, add the corresponding registration or unregistration method.

Do not suppress a warning from this rule.

The following example shows a type that violates the rule. The commented code shows the fix for the violation.

using System;
using System.Runtime.InteropServices;

[assembly: ComVisible(true)]
namespace InteroperabilityLibrary
   public class ClassToRegister

   public class ComRegistration
      internal static void RegisterFunction(Type typeToRegister) {}

//      [ComUnregisterFunction]
//      internal static void UnregisterFunction(Type typeToRegister) {}

CA1411: COM registration methods should not be visible

Registering Assemblies with COM
Regasm.exe (Assembly Registration Tool)