PB4 - Win32 - Show-API-Error ()

va!n · Post by **va!n** » Wed Apr 26, 2006 2:56 am

Code updated for 5.20+

I think some of you have tried to call any PB or API command and nothing happend. Now this small procedure may hopefully help you to find the problem

Good Luck! Feedback would be nice!

Code: Select all

;-------------------------------------------------------------------------------------
; P u r e B a s i c   v4       S h o w - A P I - E r r o r ( ) 
; ------------------------------------------------------------------------------------- 
;
; Description:    This function examines, what was wrong with the last command call by
;                 API/PB like if nothing happens again! It returns a suitable error
;                 message string in your national language!
;
; Function:       ShowAPIError (CheckReturnValue)
;
; Parameters:     CheckReturnValue 
; 
;                 Enter here the value, where you have saved the return value of the 
;                 API/PB command you have called and want to check.                  
;
; ReturnValue:    A string including the message text will be returned.
;
; ------------------------------------------------------------------------------------- 
; Program by va!n aka Thorsten Will - 26/April/2006
; ------------------------------------------------------------------------------------- 

Procedure.s ShowAPIError (CheckReturnValue)
  Buffer.s      = Space (4096)
  NumberOfChars = FormatMessage_(#FORMAT_MESSAGE_FROM_SYSTEM, 0, CheckReturnValue, 0, Buffer.s, Len(Buffer.s), 0)
  ProcedureReturn Left (Buffer.s, NumberOfChars-2)
EndProcedure

; ------------------------------------------------------------------------------------- 
; S m a l l   e x a m p l e
; ------------------------------------------------------------------------------------- 

result = Sleep_(2)
Debug ShowAPIError(result)              ; No Error 

result = RegOpenKeyEx_(0, 0, 0, 0, 0) 
Debug ShowAPIError(result)              ; Error 
         
result = MessageBox_(0,0,0,0)
Debug ShowAPIError(result)              ; Error (after pressing the MsgBox) 

;-------------------------------------------------------------------------------------

netmaestro · Post by **netmaestro** » Wed Apr 26, 2006 7:05 am

Great tip! This is going in my tools folder right away. Thanks for sharing it.

Flype · Post by **Flype** » Wed Apr 26, 2006 8:07 am

That's good, and useful.

Just a little remark : you might 'protect' variables with 'Protected' to avoid possible conflicts with main program.

Code: Select all

Procedure.s ShowAPIError (CheckReturnValue)
  Protected Buffer.s = Space (4096)
  Protected NbChar.l = FormatMessage_(#FORMAT_MESSAGE_FROM_SYSTEM, 0, CheckReturnValue, 0, Buffer, Len(Buffer), 0)
  ProcedureReturn Left(Buffer, NbChar-2)
EndProcedure

Tranquil · Post by **Tranquil** » Wed Apr 26, 2006 9:55 am

Nice! I will try it next time if I fall in such a hole without an error message from pb.

ABBKlaus · Post by **ABBKlaus** » Wed Apr 26, 2006 11:09 am

corrected Flype code :

Code: Select all

Procedure.s ShowAPIError (CheckReturnValue) 
  Protected Buffer.s
  Protected NbChar.l
  Buffer = Space(4096) 
  NbChar = FormatMessage_(#FORMAT_MESSAGE_FROM_SYSTEM, 0, CheckReturnValue, 0, Buffer, Len(Buffer), 0) 
  ProcedureReturn Left(Buffer, NbChar-2) 
EndProcedure

techjunkie · Post by **techjunkie** » Wed Apr 26, 2006 12:10 pm

ABBKlaus wrote:corrected Flype code :

Code: Select all

Procedure.s ShowAPIError (CheckReturnValue) 
  Protected Buffer.s
  Protected NbChar.l
  Buffer = Space(4096) 
  NbChar = FormatMessage_(#FORMAT_MESSAGE_FROM_SYSTEM, 0, CheckReturnValue, 0, Buffer, Len(Buffer), 0) 
  ProcedureReturn Left(Buffer, NbChar-2) 
EndProcedure

What was wrong with Flype's code?!?

In PB 4.0 B11 documentation it says,

PB Help wrote:Syntax
Protected <variable> [= <expression>], <variable> [= <expression>], ...]

Only a re-format for easy reading or?

netmaestro · Post by **netmaestro** » Wed Apr 26, 2006 12:15 pm

All the posted codes work

gnozal · Post by **gnozal** » Wed Apr 26, 2006 12:36 pm

techjunkie wrote:What was wrong with Flype's code?!?

Nothing, but not PB3.94 compatible

techjunkie · Post by **techjunkie** » Wed Apr 26, 2006 12:38 pm

gnozal wrote:
techjunkie wrote:What was wrong with Flype's code?!?
Nothing, but not PB3.94 compatible

Ahh, okey...

va!n · Post by **va!n** » Wed Apr 26, 2006 3:52 pm

thanks for the feedback

Flype · Post by **Flype** » Wed Apr 26, 2006 4:19 pm

from this topic and va!n proc, i had a little idea :
http://www.purebasic.fr/english/viewtopic.php?t=9926

Code: Select all

Procedure.l die(msg.s = #NULL$)
  If msg = #NULL$
    msg = Space(4096)
    FormatMessage_(#FORMAT_MESSAGE_FROM_SYSTEM, 0, GetLastError_(), 0, msg, Len(msg), 0)
  EndIf
  MessageRequester(GetFilePart(#PB_Compiler_File), msg, #MB_OK|#MB_ICONERROR)
EndProcedure

If ReadFile(0,"no-file.txt") Or Die()
  CloseFile(0)
EndIf

looks good, no ?

va!n · Post by **va!n** » Wed Apr 26, 2006 4:26 pm

Yes, looks nice! Its exactly for what i made the procedure

josku_x · Post by **josku_x** » Wed Apr 26, 2006 7:54 pm

Code: Select all

If ReadFile(0,"no-file.txt") Or Die() 
  CloseFile(0) 
EndIf

THat reminds me when I do SQL stuff, I always use DoSomeThing() or Die("I am idiot.")

Shardik · Post by **Shardik** » Thu Apr 27, 2006 7:33 am

Thank you va!n for your tip but I thought the use of the FormatMessage-Call is already commonly known. I myself have known and used this method already several years. Some postings from 2002:
http://www.purebasic.fr/english/viewtopic.php?t=3809
http://www.purebasic.fr/english/viewtopic.php?t=16792

va!n · Post by **va!n** » Thu Apr 27, 2006 1:59 pm

ohhh... i personally didnt know that it was already published on this forum, years ago... maybe, because i am trying now more and more to get in touch with the API instead only PB commands...

I found the tip on the web of a VB site and tried to get it work... ^^