zinpub

Yes

procedure TForm4.btnClick(Sender: TObject);
begin
  TStringList.Create;
end;

FastMM4 catches them.

Can't get log file from FastMM5...  Maybe someone can explain what I'm doing wrong?

Delphi 11

program Project4;

uses
  FastMM5,
  System.StartUpCopy,
  FMX.Forms,
  SysUtils,
  Unit4 in 'Unit4.pas' {Form4};

{$R *.res}

begin
  FastMM_LogToFileEvents := [mmetDebugBlockDoubleFree,
    mmetDebugBlockReallocOfFreedBlock, mmetDebugBlockHeaderCorruption,
    mmetDebugBlockFooterCorruption, mmetDebugBlockModifiedAfterFree,
    mmetVirtualMethodCallOnFreedObject,
    mmetAnotherThirdPartyMemoryManagerAlreadyInstalled,
    mmetCannotInstallAfterDefaultMemoryManagerHasBeenUsed,
    mmetCannotSwitchToSharedMemoryManagerWithLivePointers];

  FastMM_SetEventLogFilename('D:\log.txt');

  FastMM_EnterDebugMode;

  ReportMemoryLeaksOnShutdown := True;

  Application.Initialize;
  Application.CreateForm(TForm4, Form4);
  Application.Run;
end.

Well, the transformation of the "any - possible" date is not a task for one function 🙂

requires minimal refinement

function TForm7.StrToDateFrmt(const iFormat, iDateStr: string): TDateTime;
var
  AYear, AMonth, ADay, AHour, AMinute, ASecond, AMilliSecond: Word;
  aPos: Integer;

  procedure InitVars;
  begin
    AYear := 1;
    AMonth := 1;
    ADay := 1;
    AHour := 0;
    AMinute := 0;
    ASecond := 0;
    AMilliSecond := 0;
  end;

  function GetPart(const iPart: Char): Word;
  var
    aYCnt: Integer;
  begin
    Result := 0;
    aYCnt := 0;

    while (aPos <= High(iFormat)) and (iFormat.Chars[aPos + aYCnt] = iPart) do
      inc(aYCnt);

    Result := StrToInt(iDateStr.Substring(aPos, aYCnt));

    aPos := aPos + aYCnt;
  end;

begin
  InitVars;
  aPos := 0;

  while aPos <= High(iFormat) do
  begin
    case iFormat.Chars[aPos] of
      'Y':
        AYear := GetPart('Y');
      'M':
        AMonth := GetPart('M');
      'D':
        ADay := GetPart('D');
      'H':
        AHour := GetPart('H');
      'N':
        AMinute := GetPart('N');
      'S':
        ASecond := GetPart('S');
      'Z':
        AMilliSecond := GetPart('Z');
    else
      inc(aPos);
    end;
  end;

  Result := EncodeDateTime(AYear, AMonth, ADay, AHour, AMinute, ASecond,
    AMilliSecond);
end;

just saw !

Your SQL is 'ID Delete from Ledger ..... '   🙂

Much better use ParamByName

On 12/24/2018 at 7:50 AM, JDS2018 said:

This is the code but still same error

 

Query.SQL.Add('Delete  From Ledger');
 Query.SQL.Add('Where LedgerDate between  '''+StartDate+ '''  AND  '''+EndDate+'''');

Is there space before "Where" or after "Ledger" ?  Try print in one string ....

const

  sSql = "Delete from Ledger where LedgerDate between %s and %s";

Query.Sql.Text:= Format(sSql, ['01.01.2019', '01.01.2019']);

10 minutes ago, Alexander Elagin said:

What if those fields (TField instances) belong to some already destroyed component? Then the FieldByName references may point to some garbage. Or there are simply no fields with such names, then FieldByName returns nil and AsFloat produces an AV. Just guessing.

FieldByName raise Exception if there are no fields with such names. FindField return nil