System.Reflection.TargetInvocationException: dynamically define a constructor with parameters

Question

We want to dynamically create a class constructor, as shown below:

public JsRF1013Wrapper(ScriptEngine scriptEngine, string jsFileFullPath) { this.ScriptEngine = scriptEngine; var jsFileContent = File.ReadAllText(jsFileFullPath); this.ScriptEngine.Execute(jsFileContent); } 

we got IL:

 .method public hidebysig specialname rtspecialname instance void .ctor(class [ClearScript]Microsoft.ClearScript.ScriptEngine scriptEngine, string jsFileFullPath) cil managed { // Code size 37 (0x25) .maxstack 2 .locals init ([0] string jsFileContent) IL_0000: ldarg.0 IL_0001: call instance void [mscorlib]System.Object::.ctor() IL_0006: nop IL_0007: nop IL_0008: ldarg.0 IL_0009: ldarg.1 IL_000a: stfld class [ClearScript]Microsoft.ClearScript.ScriptEngine TotalTaxation.TaxformCalculationUnitTests.JsRF1013Wrapper::ScriptEngine IL_000f: ldarg.2 IL_0010: call string [mscorlib]System.IO.File::ReadAllText(string) IL_0015: stloc.0 IL_0016: ldarg.0 IL_0017: ldfld class [ClearScript]Microsoft.ClearScript.ScriptEngine TotalTaxation.TaxformCalculationUnitTests.JsRF1013Wrapper::ScriptEngine IL_001c: ldloc.0 IL_001d: callvirt instance void [ClearScript]Microsoft.ClearScript.ScriptEngine::Execute(string) IL_0022: nop IL_0023: nop IL_0024: ret } // end of method JsRF1013Wrapper::.ctor 

we wrote the emit code: ConstructorInfo objCtor = calculatorType.GetConstructor (new type [] {typeof (ScriptEngine), typeof (string)});

 Type[] ctorParams = new Type[] { typeof(ScriptEngine), typeof(string) }; ConstructorBuilder wrapperCtor = typeBuilder.DefineConstructor( MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.SpecialName | MethodAttributes.RTSpecialName, CallingConventions.Standard, ctorParams); ILGenerator ctorIL = wrapperCtor.GetILGenerator(); ctorIL.Emit(OpCodes.Ldarg_0); ctorIL.Emit(OpCodes.Call, objCtor); ctorIL.Emit(OpCodes.Nop); ctorIL.Emit(OpCodes.Nop); ctorIL.Emit(OpCodes.Ldarg_0); ctorIL.Emit(OpCodes.Ldarg_1); ctorIL.Emit(OpCodes.Stfld, scriptEngineField); ctorIL.Emit(OpCodes.Ldarg_2); ctorIL.Emit(OpCodes.Call, typeof(File).GetMethod("ReadAllText", new Type[] { typeof(string) })); ctorIL.Emit(OpCodes.Stloc_0); ctorIL.Emit(OpCodes.Ldarg_0); ctorIL.Emit(OpCodes.Ldfld, scriptEngineField); ctorIL.Emit(OpCodes.Ldloc_0); ctorIL.Emit(OpCodes.Callvirt, typeof(ScriptEngine).GetMethod("Execute", new Type[] { typeof(string) })); ctorIL.Emit(OpCodes.Nop); ctorIL.Emit(OpCodes.Nop); ctorIL.Emit(OpCodes.Stfld, jsFileFullPathField); ctorIL.Emit(OpCodes.Ret); 

and there is an exception called System.Reflection.TargetInvocationException when used as follows:

 ICalculator calculator = (ICalculator)Activator.CreateInstance(t, new object[] { new JScriptEngine(), jsFileFullPath }); 

what problem?