[Last Call] Learn how to a build a cloud-first strategyRegister Now

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 3085
  • Last Modified:

Convert Int64 to Int32 (Integer) ?

Is it possible to convert int64 to in32 in delphi ?
0
rotem156
Asked:
rotem156
2 Solutions
 
Geert GruwezOracle dbaCommented:
calculate the percentage of the completion ... a lot easier for the progressbar
you only get numbers from 0 to 100
0
 
epasquierCommented:
first, use 1Gb parts, it will be a lot easier.

procedure Split1GoParts(TotalSize:Int64;Var NbFullParts,LastIncompletePartSize:Integer):
begin
 NbFullParts:=TotalSize SHR 30;
 LastIncompletePartSize:=TotalSize And $3FFFFFFF;
end;

Open in new window


then,in your thread Create, instead of using an EndOffset, use a Part Size to download (Integer).
You'll end up with a much cleaner thread code and an easier way to create those threads (only ONE int64 value is needed, the offset):
Somewhere in your code you'll have to use what Split1GoParts returns :

PartSize:=1 SHL 30;
for i:=0 to NbFullParts-1 do
 CreateThread ( alabel[I], apbar[I], hOpenFile[I], hInetFile[I], i*PartSize, PartSize);

Open in new window

Where CreateThread function is of course something that creates the thread and add it to your manager.
TFetchDataThread = class(TThread)
  private
    FStartOffset    : Int64;
    FPartSize       : Integer;
    FInetFile       : HINTERNET;
    FDestFile       : THandle;
    FProgressBar    : TProgressBar;
    FLabelProgress  : TLabel;
    FLoadedSize     : Integer;
    procedure ProgressGui;
  protected
    procedure Execute; override;
  public
    constructor Create(
    LabelProgress : TLabel;
    Progress      : TProgressBar;
    DestFile      : THandle;
    InetFile      : HINTERNET;
    StartOffset  : Int64;
    PartSize    : Integer);
    destructor Destroy;
  end;


constructor TFetchDataThread.Create(
LabelProgress: TLabel;
Progress     : TProgressBar;
DestFile     : THandle;
InetFile     : HINTERNET;
StartOffset  : Int64;
PartSize    : Integer);
begin
  FStartOffset    := StartOffset;
  FPartSize       := PartSize;
//  FEndOffset      := EndOffset;
  FInetFile       := InetFile;
  FDestFile       := DestFile;
  FProgressBar    := Progress;
  FLabelProgress  := LabelProgress;
  inherited Create( {DAPClass.UpdateProgressBar,} False );
end;

procedure TFetchDataThread.ProgressGui;
begin
  FProgressBar.Value := FLoadedSize;
  FProgressBar.Repaint; // Avoid gui problems
  FLabelProgress.Text :=
  Format( 'Thread: %d, Start Offset: %d (%x h), Loaded %d / %d (%f %%)',
   [ThreadID, FStartOffset, FStartOffset, FLoadedSize, FPartSize, 100*FLoadedSize/FPartSize ] );
end;

procedure TFetchDataThread.Execute;
type
  TypeByteArray = array [1..1024*2] of Byte;
var
  Buffer            : TypeByteArray;
  BytesToReadWrite,
  BufferLen,
  BytesWritten,
begin
 FreeOnTerminate := True;
 FProgressBar.Min :=  0;
 FProgressBar.Max :=  FPartSize;
 InternetSetFilePointer( FInetFile, FStartOffset, nil, FILE_BEGIN, 0 );
 SetFilePointer( FDestFile, FStartOffset, nil, FILE_BEGIN );
 try
  repeat
   BytesToReadWrite := FPartSize - FLoadedSize;
   if BytesToReadWrite > SizeOf( Buffer ) 
     Then BytesToReadWrite  := SizeOf( Buffer )

   InternetReadFile( FInetFile, @Buffer, BytesToReadWrite, BufferLen );

   LockFile( FDestFile, FStartOffset, 0, BytesToReadWrite, 0 );
   WriteFile( FDestFile, Buffer, BytesToReadWrite, BytesWritten, nil );
   UnlockFile( FDestFile, FStartOffset, 0, BytesToReadWrite, 0 );
   Inc(FLoadedSize,BytesWritten);
   
   Synchronize( ProgressGui );

// Why reducing CPU in the download thread ? it will just slow down everything.
//    Sleep( Random( 15 ) ); // Avoid cpu usage
  until (FLoadedSize>=FPartSize) or (Terminated);
 finally
  CloseHandle( FDestFile );
  InternetCloseHandle( FInetFile );
 end;
end;

Open in new window

0

Featured Post

Concerto's Cloud Advisory Services

Want to avoid the missteps to gaining all the benefits of the cloud? Learn more about the different assessment options from our Cloud Advisory team.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now