AssemblyName.KeyPair Property

Definition

Caution

Strong name signing is not supported and throws PlatformNotSupportedException.

Gets or sets the public and private cryptographic key pair that is used to create a strong name signature for the assembly.

public System.Reflection.StrongNameKeyPair? KeyPair { get; set; }
[System.Obsolete("Strong name signing is not supported and throws PlatformNotSupportedException.", DiagnosticId="SYSLIB0017", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
public System.Reflection.StrongNameKeyPair? KeyPair { get; set; }
public System.Reflection.StrongNameKeyPair KeyPair { get; set; }

Property Value

The public and private cryptographic key pair to be used to create a strong name for the assembly.

Attributes

Exceptions

.NET 6+ only: In all cases.

Examples

The following example emits a dynamic assembly and saves it to the current directory. When the assembly is created, the KeyPair property is used to set the assembly's public and private cryptographic keys.


using System;
using System.Reflection;
using System.Threading;
using System.IO;
using System.Globalization;
using System.Reflection.Emit;
using System.Configuration.Assemblies;
using System.Text;

public class AssemblyName_CodeBase
{
   public static void MakeAssembly(AssemblyName myAssemblyName, string fileName)
   {
      // Get the assembly builder from the application domain associated with the current thread.
      AssemblyBuilder myAssemblyBuilder = Thread.GetDomain().DefineDynamicAssembly(myAssemblyName, AssemblyBuilderAccess.RunAndSave);
      // Create a dynamic module in the assembly.
      ModuleBuilder myModuleBuilder = myAssemblyBuilder.DefineDynamicModule("MyModule", fileName);
      // Create a type in the module.
      TypeBuilder myTypeBuilder = myModuleBuilder.DefineType("MyType");
      // Create a method called 'Main'.
      MethodBuilder myMethodBuilder = myTypeBuilder.DefineMethod("Main", MethodAttributes.Public | MethodAttributes.HideBySig |
         MethodAttributes.Static, typeof(void), null);
      // Get the Intermediate Language generator for the method.
      ILGenerator myILGenerator = myMethodBuilder.GetILGenerator();
      // Use the utility method to generate the IL instructions that print a string to the console.
      myILGenerator.EmitWriteLine("Hello World!");
      // Generate the 'ret' IL instruction.
      myILGenerator.Emit(OpCodes.Ret);
      // End the creation of the type.
      myTypeBuilder.CreateType();
      // Set the method with name 'Main' as the entry point in the assembly.
      myAssemblyBuilder.SetEntryPoint(myMethodBuilder);
      myAssemblyBuilder.Save(fileName);
   }

   public static void Main()
   {
      // Create a dynamic assembly with name 'MyAssembly' and build version '1.0.0.2001'.
      AssemblyName myAssemblyName = new AssemblyName();
      // Set the codebase to the physical directory were the assembly resides.
      myAssemblyName.CodeBase = Directory.GetCurrentDirectory();
      // Set the culture information of the assembly to 'English-American'.
      myAssemblyName.CultureInfo = new CultureInfo("en-US");
      // Set the hash algorithm to 'SHA256'.
      myAssemblyName.HashAlgorithm = AssemblyHashAlgorithm.SHA256;
      myAssemblyName.VersionCompatibility = AssemblyVersionCompatibility.SameProcess;
      myAssemblyName.Flags = AssemblyNameFlags.PublicKey;
      // Provide this assembly with a strong name.
      myAssemblyName.KeyPair = new StrongNameKeyPair(File.Open("KeyPair.snk", FileMode.Open, FileAccess.Read));
      myAssemblyName.Name = "MyAssembly";
      myAssemblyName.Version = new Version("1.0.0.2001");
      MakeAssembly(myAssemblyName, "MyAssembly.exe");

      // Get the assemblies loaded in the current application domain.
      Assembly[] myAssemblies = Thread.GetDomain().GetAssemblies();

      // Get the dynamic assembly named 'MyAssembly'.
      Assembly myAssembly = null;
      for(int i = 0; i < myAssemblies.Length; i++)
         if(String.Compare(myAssemblies[i].GetName().Name, "MyAssembly") == 0)
            myAssembly = myAssemblies[i];

      // Display the full assembly information to the console.
      if(myAssembly != null)
      {
         Console.WriteLine("\nDisplaying the full assembly name.\n");
         Console.WriteLine(myAssembly.GetName().FullName);
         Console.WriteLine("\nDisplaying the public key.\n");
         byte []pk;
         pk = myAssembly.GetName().GetPublicKey();
         for (int i=0;i<pk.GetLength(0);i++)
            Console.Write ("{0:x2}", pk[i]);
         Console.WriteLine();
         Console.WriteLine("\nDisplaying the public key token.\n");
         byte []pt;
         pt = myAssembly.GetName().GetPublicKeyToken();
         for (int i=0;i<pt.GetLength(0);i++)
            Console.Write ("{0:x2}", pt[i]);
      }
   }
}

Remarks

When the runtime loads an assembly, it does not set the KeyPair property. The getter for the property is only useful if the user set the property before using the AssemblyName object to create a dynamic assembly, and subsequently wants to retrieve the key pair.

Applies to

Product Versions (Obsolete)
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5 (6, 7, 8, 9)
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1