Pascal (Lazarus/Delphi)

Enter/Leave Context in Logging

Demonstrates EnterContext and LeaveContext using the Chilkat Log API. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Log;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  log: TLog;

begin
  log := TLog.Create;

  //  Initialize the log object with an initial context tag:
  log.Clear('myLog');

  //  Add some information..
  log.LogInfo('Hello, I''m here...');

  //  Open a sub-context
  log.EnterContext('abc');

  //  New information is now logged within the "abc" context.
  log.LogInfo('This is inside the abc context');
  log.LogError('File not found.');

  //  Perhaps open a new context...
  log.EnterContext('fileInfo');
  log.LogData('filename','something.txt');
  log.LogData('path','/somedir/xyz');
  log.LeaveContext();

  //  Close the "abc" context.
  log.LeaveContext();

  //  Examine the content of the log:
  WriteLn(log.LastErrorText);

  //  This is the output:

  //  myLog:
  //    Hello, I'm here...
  //    abc:
  //      This is inside the abc context
  //      File not found.
  //      fileInfo:
  //        filename: something.txt
  //        path: /somedir/xyz
  //      --fileInfo
  //    --abc
  //  --myLog


  log.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.