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Can a method return some value in ATL Active-X Dll

Posted on 2002-03-28
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Last Modified: 2013-11-25
Hi ,

My Question is that I have made an ATL COM Dll.I have only one method in that Dll.Can my method return Boolean Value.

If Yes ,then HOW????????????????
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Question by:goodami
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4 Comments
 
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Expert Comment

by:pkreddy
ID: 6902107
Hi,
 Try the following things.

  1. Declare a [in,out] value with a BOOL* var. Make necessary changes to your IDL file and your header, implementation files.
  2. Now in your source code in function, you assign the required boolean value to the var declaredabove.
   
  COM automatically returns you back the BOOL value you assigned in the DLL to the cleint when the function call is made.
regards,
Pavan
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LVL 6

Expert Comment

by:snoegler
ID: 6902165
[out, retval]
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Accepted Solution

by:
snoegler earned 50 total points
ID: 6902170
Sample:

[helpstring("blabla")] HRESULT DoSomething([in] long lInput, [out, retval] long *pResult);

VB-Call of sample method:

Dim res as long
res = obj.DoSomething(123);
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LVL 1

Expert Comment

by:pkreddy
ID: 6902179
Snoegler is right, i made a mistake there. The parameter must be marked as [out,retval] in your IDL file
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