EHTrial.cs

using System;
using System.Collections.Generic;
using System.Reflection;
using System.Reflection.Emit;

namespace EHTrial
{
    class Program
    {
        static void Main(string[] args)
        {
            var pMSCorLib = Assembly.Load("mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, processorArchitecture=x86");

            var pMSCorLibDll = pMSCorLib.GetModule("CommonLanguageRuntimeLibrary");

            var pVoid = pMSCorLibDll.GetType("System.Void");
            var pInt32 = pMSCorLibDll.GetType("System.Int32");
            var pString = pMSCorLibDll.GetType("System.String");
            var pStreamReader = pMSCorLibDll.GetType("System.IO.StreamReader");
            var pChar = pMSCorLibDll.GetType("System.Char");
            var pIOException = pMSCorLibDll.GetType("System.IO.IOException");
            var pTextReader = pMSCorLibDll.GetType("System.IO.TextReader");
            var pException = pMSCorLibDll.GetType("System.Exception");
            var pConsole = pMSCorLibDll.GetType("System.Console");
            var pObject = pMSCorLibDll.GetType("System.Object");

            var pStreamReader_ctor_string = default(ConstructorInfo);
            {
                var @params = new List<Type>();
                @params.Add(pString);
                pStreamReader_ctor_string = pStreamReader.GetConstructor(@params.ToArray());
            }
            var pTextReader_ReadBlock_CharArr_Int32_Int32 = default(MethodInfo);
            {
                var @params = new List<Type>();
                @params.Add(pChar.MakeArrayType());
                @params.Add(pInt32);
                @params.Add(pInt32);
                pTextReader_ReadBlock_CharArr_Int32_Int32 = pTextReader.GetMethod("ReadBlock", @params.ToArray());
            }
            var pTextReader_Close = pTextReader.GetMethod("Close");
            var pException_get_Message = pException.GetMethod("get_Message");
            var pConsole_WriteLine_string_object_object = default(MethodInfo);
            {
                var @params = new List<Type>();
                @params.Add(pString);
                @params.Add(pObject);
                @params.Add(pObject);
                pConsole_WriteLine_string_object_object = pConsole.GetMethod("WriteLine", @params.ToArray());
            }

            var pMSCorLibEHGen = AppDomain.CurrentDomain.DefineDynamicAssembly(new AssemblyName("mscorlib.EH"), AssemblyBuilderAccess.RunAndSave);

            var pMSCorLibEHDllGen = pMSCorLibEHGen.DefineDynamicModule("mscorlib.EH.dll");

            var pEHClassGen = pMSCorLibEHDllGen.DefineType("mscorlib.Prig.EHClass",
                                                           TypeAttributes.Public |
                                                           TypeAttributes.AutoClass |
                                                           TypeAttributes.AnsiClass |
                                                           TypeAttributes.BeforeFieldInit);

            var pEHClassGen_ReadFile = default(MethodBuilder);
            {
                var @params = new List<Type>();
                @params.Add(pString);
                @params.Add(pInt32);
                pEHClassGen_ReadFile = pEHClassGen.DefineMethod("ReadFile",
                                                                MethodAttributes.Public |
                                                                MethodAttributes.HideBySig,
                                                                CallingConventions.Standard,
                                                                pVoid,
                                                                @params.ToArray());
            }

            {
                var pBodyGen = pEHClassGen_ReadFile.GetILGenerator();

                var pLocal0_file = pBodyGen.DeclareLocal(pStreamReader);
                var pLocal1_buffer = pBodyGen.DeclareLocal(pChar.MakeArrayType());
                var pLocal2_e = pBodyGen.DeclareLocal(pIOException);

                var label0 = pBodyGen.DefineLabel();

                pBodyGen.Emit(OpCodes.Ldnull);
                pBodyGen.Emit(OpCodes.Stloc_0);
                pBodyGen.Emit(OpCodes.Ldc_I4_S, (byte)10);
                pBodyGen.Emit(OpCodes.Newarr, pChar);
                pBodyGen.Emit(OpCodes.Stloc_1);

                pBodyGen.BeginExceptionBlock();
                {
                    pBodyGen.Emit(OpCodes.Ldarg_1);
                    pBodyGen.Emit(OpCodes.Newobj, pStreamReader_ctor_string);
                    pBodyGen.Emit(OpCodes.Stloc_0);
                    pBodyGen.Emit(OpCodes.Ldloc_0);
                    pBodyGen.Emit(OpCodes.Ldloc_1);
                    pBodyGen.Emit(OpCodes.Ldarg_2);
                    pBodyGen.Emit(OpCodes.Ldloc_1);
                    pBodyGen.Emit(OpCodes.Ldlen);
                    pBodyGen.Emit(OpCodes.Conv_I4);
                    pBodyGen.Emit(OpCodes.Callvirt, pTextReader_ReadBlock_CharArr_Int32_Int32);
                    pBodyGen.Emit(OpCodes.Pop);
                }
                pBodyGen.BeginCatchBlock(pIOException);
                {
                    pBodyGen.Emit(OpCodes.Stloc_2);
                    pBodyGen.Emit(OpCodes.Ldstr, "Error reading from {0}. Message = {1}");
                    pBodyGen.Emit(OpCodes.Ldarg_1);
                    pBodyGen.Emit(OpCodes.Ldloc_2);
                    pBodyGen.Emit(OpCodes.Callvirt, pException_get_Message);
                    pBodyGen.Emit(OpCodes.Call, pConsole_WriteLine_string_object_object);
                }
                pBodyGen.BeginFinallyBlock();
                {
                    pBodyGen.Emit(OpCodes.Ldloc_0);
                    pBodyGen.Emit(OpCodes.Brfalse_S, label0);
                    pBodyGen.Emit(OpCodes.Ldloc_0);
                    pBodyGen.Emit(OpCodes.Callvirt, pTextReader_Close);
                    pBodyGen.MarkLabel(label0);
                }
                pBodyGen.EndExceptionBlock();

                pBodyGen.Emit(OpCodes.Ret);
            }

            pEHClassGen.CreateType();

            pMSCorLibEHGen.Save("mscorlib.EH.dll", PortableExecutableKinds.ILOnly, ImageFileMachine.I386);
        }
    }
}