Object of type 'System.Int32' cannot be converted to type 'System.Object[]'

Rightthen

18y25.5kC#

GentleMen

Object of type 'System.Int32' cannot be converted to type 'System.Object[]'.
Is The Error I am Getting In c#.
I need Immediate Remedy Please

class SomeClass
{

public delegate void SomeDel ( params object[] Params_list );

public void SomeFunc(params object[] Params_List)
{
  // Updates Value Of Some Treeview According To Value Recieved
}

public void SomeThreadFunc()
{
   SomeDel a ;

   a = SomeFunc ;

   object[] Params_List = new object[1];

   Params_List.setvalue(0,1);

   this.invoke( a, Params_List); // Here Is Where Comes The Error
                                 // Althou i Have Tried new object[] {1}
                                 // but with no respite
  
}
 
}

It Compiles Well But While Runing It Creates Problems
what am i doing wrong how to go about it

Thankyou
RIGHT_THEN

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Alan18y ago
Accepted answer
Well, the 'standard' solution here would be:

this.Invoke(a, new object[]{Params_List});

because the second parameter of Invoke is an object array of parameters to the 'a' delegate and the first (and only) such parameter is itself an object array.

However, the reason why the following also works:

this.Invoke(a, (object)Params_List);

is because the second parameter to Invoke is a parameter array and you can therefore supply it with a list of object references (in this case just one) rather than an object array reference. Moreover, because all types inherit from object then (somewhat paradoxically) even an object[] can be cast to an object!
tot2ivn18y ago
Thank you guys !! It solved my problem too. :)

Totti
Rightthen18y ago
Sir Mr. Dr. Spack

You were Right!!! Althou i had placed and checked the code before too

but when it gets multithreaded control remains in the primary thread

while debugging unless we place a breakpoint in secondary thread too

so i placed try and catcth in secondary thread too

and there the culprit was found. Your Diagnostic about the situation was

right and comes as a lesson to me that debugging mulithreaded application

could be problemetic.

i think i will have to make all those mistakes again

just to be sure if they actually were mistakes since the bug has been found.

That i had not discarded the right things for wrong at some other place.

Regards and million thanks

Gratefully

RIGHT_THEN
Dr Spack18y ago
Hi RIGHT_THEN,

I think that the Invoke call is just working
and your function (SomeFunc) does throw that
exception.

So I would set a breakpoint in that function and debug it.
Or add a try-catch block to check that out.
Dr Spack18y ago
Hi Alan,

it took me a while, but now I've got it. ;)

Thank you!
Dr Spack18y ago
Hi,

that is a strange thing, but I have a solution:
this.Invoke( a, (object)Params_List );

Just add (object) and it will work! Why? I don't know. Maybe someone else does know an explanation for that!?