Marc,
I tried your solution but still get the error message:
""This program has performed an illegal operation and will be shut down...
yada.. yada. yada..."
Here's my sample MB code...
Is there anything obviously wrong?
-----------------------------------------------------------------
Include "MAPBASIC.DEF"
Declare Sub ChangeValue Lib "Project_PCharAlternative.DLL"
Alias "ChangeValue"
(FName as String, LName as String)
Declare Sub Main
'**********************************************************
Sub Main
Dim
FName as String,
LName as String
FName = Space$(100)
LName = Space$(100)
FName = "Mapinfo First Name"
LName = "Mapinfo Last Name"
Note FName + chr$(13) + LName
call ChangeValue(FName, LName)
Note FName + chr$(13) + LName
End Sub
-----------------------------------------------------------------
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Marc Pelletier
Sent: Wednesday, 17 January 2001 2:06 AM
To: [EMAIL PROTECTED]
Subject: Re: MI-L MB/Delphi - Passing strings from MB to Delphi DLL
(revisited)
Peter,
There's nothing obviously wrong with the function below, and I've done the
same thing numerous times. It's good practice, though, to pass the lengths
of the pchars as well so that you can ensure you're not overwriting
something. That's probably what's happening here.
I'm really not sure how your record type works, given that the pchars could
be any length, in that case I would use an array of char with fixed length.
One way to modify the function so you can be sure you're not overwriting
anything is as follows:
procedure ChangeValue(var FName:PChar; var LName:PChar);
begin
StrLcopy( FName, 'Delphi First Name', sizeof( FName ) - 1 );
StrLcopy( LName, 'Delphi Last Name', sizeof( LName ) - 1 );
end;
Knocking 1 off of the length ensures that if FName is null terminated to
begin with it will remain so.
Hope this helps.
Marc Pelletier
Traxis Inc.
At 12:51 PM 5/23/01 +1000, you wrote:
>procedure ChangeValue(var FName:PChar; var LName:PChar); Stdcall;
>
>implementation
>
>//******************************************************
>procedure ChangeValue(var FName:PChar; var LName:PChar);
>begin
> StrPcopy(FName,'Delphi First Name'); //<--Everything crashes in a
great
>heap!
> StrPcopy(LName,'Delphi Last Name');
>end;
>//******************************************************
>end.
_______________________________________________________________________
List hosting provided by Directions Magazine | www.directionsmag.com |
To unsubscribe, send e-mail to [EMAIL PROTECTED] and
put "unsubscribe MapInfo-L" in the message body.
_______________________________________________________________________
List hosting provided by Directions Magazine | www.directionsmag.com |
To unsubscribe, send e-mail to [EMAIL PROTECTED] and
put "unsubscribe MapInfo-L" in the message body.
