' 导入命名空间
Imports System.IO
Imports System.Reflection
Imports System.Reflection.Emit

Module Test
   
   Sub Main()
      Dim currentDomain As AppDomain = AppDomain.CurrentDomain
      
      InstantiateMyType(currentDomain)      ' Failed!

      AddHandler currentDomain.AssemblyResolve, AddressOf MyResolver
      
      InstantiateMyType(currentDomain)      ' OK!
   End Sub
   
   
   Sub InstantiateMyType(domain As AppDomain)
      Try
     ' You must supply a valid fully qualified assembly name here.
         domain.CreateInstance("Assembly text name, Version, Culture, PublicKeyToken", "MyType")
      Catch e As Exception
         Console.WriteLine(e.Message)
      End Try
   End Sub
   
   
   ' Loads the content of a file to a byte array. 
   Function loadFile(filename As String) As Byte()
      Dim fs As New FileStream(filename, FileMode.Open)
      Dim buffer(CInt(fs.Length - 1)) As Byte
      fs.Read(buffer, 0, buffer.Length)
      fs.Close()
      
      Return buffer
   End Function 'loadFile
   
   
   Function MyResolver(sender As Object, args As ResolveEventArgs) As System.Reflection.Assembly
      Dim domain As AppDomain = DirectCast(sender, AppDomain)
      
      ' Once the files are generated, this call is
      ' actually no longer necessary.
      EmitAssembly(domain)
      
      Dim rawAssembly As Byte() = loadFile("temp.dll")
      Dim rawSymbolStore As Byte() = loadFile("temp.pdb")
      Dim myAssembly As System.Reflection.Assembly = domain.Load(rawAssembly, rawSymbolStore)
      
      Return myAssembly
   End Function 'MyResolver
   
   
   ' Creates a dynamic assembly with symbol information
   ' and saves them to temp.dll and temp.pdb
   Sub EmitAssembly(domain As AppDomain)
      Dim assemblyName As New AssemblyName()
      assemblyName.Name = "MyAssembly"
      
      Dim assemblyBuilder As AssemblyBuilder = domain.DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.Save)
      Dim moduleBuilder As ModuleBuilder = assemblyBuilder.DefineDynamicModule("MyModule", "temp.dll", True)
      Dim typeBuilder As TypeBuilder = moduleBuilder.DefineType("MyType", TypeAttributes.Public)
      
      Dim constructorBuilder As ConstructorBuilder = typeBuilder.DefineConstructor(MethodAttributes.Public, CallingConventions.Standard, Nothing)
      Dim ilGenerator As ILGenerator = constructorBuilder.GetILGenerator()
      ilGenerator.EmitWriteLine("MyType instantiated!")
      ilGenerator.Emit(OpCodes.Ret)
      
      typeBuilder.CreateType()
      
      assemblyBuilder.Save("temp.dll")
   End Sub

End Module 'Test