InvalidProgramException when creating a Timer using a delegate created by reflection

Asked May 05 '12 at 17:25

Active May 06 '12 at 00:46

Viewed 133 times

This code:

var returnType = GetDelegateReturnType(typeof(TimerCallback));
var methodParameters = typeof(TimerCallback).GetMethod("Invoke").GetParameters().Select(x => x.ParameterType).ToArray();

var handler = new System.Reflection.Emit.DynamicMethod("", returnType, methodParameters, typeof(ArgumentNullTest));
var generator = handler.GetILGenerator();

generator.Emit(System.Reflection.Emit.OpCodes.Ldloc, 1);
generator.Emit(System.Reflection.Emit.OpCodes.Ret);

var timerCallback = (TimerCallback)handler.CreateDelegate(typeof(TimerCallback));
var timer = new Timer(timerCallback, null, 0, 0);
var timer2 = new Timer(o => { }, null, 0, 0);

throws an InvalidProgramException when creating the second timer. What am I doing wrong when creating the TimerCallback per reflection?

edited May 06 '12 at 00:46

Omar

16,329
10
48
66

asked May 05 '12 at 17:25

Papa Mufflon

17,558
5
27
35

1

It is bad code, it unbalances the stack. LdLoc but it doesn't get used. – Hans Passant May 05 '12 at 17:34
Oh - true, true: deleting the line with the Ldloc prevents the exception. – Papa Mufflon May 05 '12 at 18:08

InvalidProgramException when creating a Timer using a delegate created by reflection

0 Answers0