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mandoza

Registriert seit: 27. Apr 2018
16 Beiträge
 
#8

AW: Update/Delete Record items in a Stream

  Alt 27. Apr 2018, 12:55
Can you post your real code? Your current LoadFromStream() and SaveToStream() appear to be testing routines because they contain syntax errors and, in their current form, do not make sense:

In LoadFromStream() you load your data into a local variable myRec . After that, your procedure ends and myRec is gone. You can inspect myRec in the debugger, but in the end, this method accomplishes nothing.

"Real code" would, for example, take an instance of TMyrecord and a filename as parameters for LoadFromStream() and SaveToStream()
Thank you , i don't have an issue with LoadFromStream() and SaveToStream() , because i'll use my Rec else where , my issue now is with updating MyRec value then save it again ( at same stream position ) . thank you again

Delphi-Quellcode:
procedure UpdateMyRecLastName(NewLastName:string);
var
  LoadingStream: TFileStream;
  i, j: Integer;
  myRec:Tmyrecord;
begin
  SavingStream := TFileStream.Create('SAVE.test', fmCreate or fmOpenWrite or fmShareDenyWrite);
  try
       myRec.LastName := ReadStringFromStream(SavingStream); // load the OLD value
       myRec.LastName:=NewLastName; // update it
      
      {
    Here how to update myRec.LastName value in the LoadingStream
      }

    
  finally
    SavingStream.Free;
  end;
end;

Geändert von mandoza (27. Apr 2018 um 12:59 Uhr)
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