define application release mode or debug mode

[Prakash]

{$DEFINE DEBUG}
        with TFileStream.Create('d:\data.json', fmCreate) do
        begin
          try
            S := datajson.AsJSON;
            WriteBuffer(S[1], Length(S));
          finally
            Free;
          end;
        end;
        {$IFDEF RELEASE}
        {$ENDIF}   

I want to execute this code only my application is in debug mode .

how and where to define application debug or release mode

[TRon]

https://wiki.lazarus.freepascal.org/IDE_Window:_Compiler_Options#Build_modes
https://wiki.freepascal.org/Conditional_compilation

[Eugene Loza]

Or to be a bit more specific:

1. Create Debug/Release mode as shown in the first link.
2. Create a custom options entry as shown a bit below that (see attached screenshot) - it will affect only the currently selected one.

your code won't compile though, {$IFDEF} needs a matching {$ENDIF}. I.e. something like:

Code: Pascal  [Select][+][-]

1. {$IFDEF DEBUG}
2. with TFileStream.Create('d:\data.json', fmCreate) do
3. begin
4.   try
5.     S := datajson.AsJSON;
6.     WriteBuffer(S[1], Length(S));
7.   finally
8.     Free;
9.   end;
10. end;
11. {$ELSE}
12.   //Do something in not-debug mode
13. {$ENDIF}

[Thaddy]

The correct option is

Code: Pascal  [Select][+][-]

1. {$ifopt d+}

This can be used with any global compiler directive, btw.
{$ifopt <x>+/-} can be used multiple times.

[Warfley]

The correct option is

Code: Pascal  [Select][+][-]

1. {$ifopt d+}

This can be used with any global compiler directive, btw.

This is not a debug mode, this is for when debug symbols are present, which you may also want to have in the release build of your program, e.g. to do logging, or for performance measurements. If your goal is to have code that is only in a debug build, you should create a debug build with a define.

[Thaddy]

Wrong.
It is equivalent to specify -dDEBUG on the command line.
The advantage is that it can be used for any global compiler directive.
I thought you knew that? Rather basic since tp days.