Zeoslib Portal

Code: Select all

procedure mtLoadFromStream(mt: TZMemTable; AStream: TStream);

  function ReadInt: longint;
  begin
    AStream.Read(result, Sizeof(longint));
  end;

var
  len, ftype, a, b, kk: Integer;  tx: string;  req: Boolean;
begin
  with mt, AStream do
  begin
    //CheckInactive;
    mt.Close;

    FieldDefs.Clear;
    DisableControls;
    AStream.Position:= 0;
    kk := ReadInt;  //fieldcount
    try
      for a := 0 To kk - 1 do
        begin
          tx := ReadAnsiString;
          ftype := ReadInt;
          len := ReadInt;
          req := ReadInt > 0;  // required field if boolean value > 0
          FieldDefs.Add(tx, TFieldType(fType), len, req);
        end;

        Open;  // Open - setup fields structure for memtable

      kk := ReadInt; // recordcount
      for a := 0 to kk-1 do
        begin
          mt.Append;
          for b := 0 to FieldCount - 1 do
            begin
              tx := AStream.ReadAnsiString;
              Fields[b].AsString := tx
            end;
          mt.Post;
        end;
      First;
    finally
      EnableControls;
    end;
  end;
end;



procedure  mtSaveToStream(mt: TZMemTable; AStream: TStream);

  procedure WriteInt(ii: longint);
  begin
    AStream.Write(ii, Sizeof(longint))
  end;

var bm: TBookMark; a: Integer; 
begin
  with mt, AStream do
  begin
    if not active then exit;
    // CheckActive;
    bm := GetBookmark;
    AStream.Position:= 0;
    try
      DisableControls;
      try
        WriteInt(FieldDefs.Count);
        for a := 0 To FieldDefs.Count - 1 do
          begin
            WriteAnsiString(FieldDefs[a].Name);
            WriteInt(Integer(FieldDefs[a].DataType));
            WriteInt(FieldDefs[a].Size);
            WriteInt(ord(FieldDefs[a].Required));
          end;
        First;
        WriteInt(RecordCount);
        while not Eof Do
          begin
            for a := 0 To FieldCount - 1 Do
              WriteAnsiString(Fields[a].AsString);
            Next;
          end;
      finally
        EnableControls;
      end;
    finally
      GotoBookmark(bm);
    end;
  end;
end;

Code: Select all

function TBlobField.GetDataSize: Integer;
begin
  // Blob data is not stored in the record buffer and can not be read
  // with a call to TField.GetData. Use GetBlobSize instead.
  Result := 0;
end;

Code: Select all

 If ZMemTable1.FieldByName('Test').IsBlob Then
   a := (ZMemTable1.FieldByName('Test') As TBlobField).BlobSize
 Else
   a := ZMemTable1.FieldByName('Test').DataSize;

Code: Select all

begin
 ZMemTable1.FieldDefs.Add('Test', ftWideMemo);

 ZMemTable1.Open;

 ZMemTable1.Append;
 ZMemTable1.FieldByName('Test').AsString := 'Hello';
 ZMemTable1.Post;

 ms := TMemoryStream.Create;
 Try
   ZMemTable1.SaveToStream(ms);

   ZMemTable1.Close;

   ms.Position := 0;
   ZMemTable1.LoadFromStream(ms);
 Finally
   FreeAndNil(ms);
 End;

Code: Select all

17:53:44 ZMemTable.pas(787) Error: (2017) $ENDIF expected for $IFDEF ZMEMTABLE_ENABLE_STREAM_EXPORT_IMPORT defined in ZMemTable.pas line 640
17:53:44 ZMemTable.pas(787)  (2033) ENDIF ZMEMTABLE_ENABLE_STREAM_EXPORT_IMPORT found
17:53:44 ZMemTable.pas(787) Fatal: (2000) Unexpected end of file

Code: Select all

procedure TZAbstractMemTable.LoadFromStream(AStream: TStream);
var
  len, ftype, a, b, cc, kk: Integer;  tx: string;  req: Boolean;
  ms: TMemoryStream;  tb: TBytes;


  function ReadInt: longint;
  begin
    AStream.ReadBuffer(result, Sizeof(longint));
  end;

  function ReadStr: string;
  begin
    cc := ReadInt;
    SetLength(result, cc);
    AStream.Readbuffer(Pointer(result)^, cc);
  end;

  procedure ReadBlob;
  begin
    ms := TMemoryStream.Create;
    ms.CopyFrom(AStream, abs(cc));
   (Fields[b] as TBlobField).LoadFromStream(ms);
    ms.Free;
  end;

  procedure ReadData;
  begin
    SetLength(tb, cc);
    AStream.ReadBuffer(Pointer(tb)^, cc);
    Fields[b].SetData(Pointer(tb));
  end;

begin
    CheckInactive;
    //Close;

    FieldDefs.Clear;
    DisableControls;
    AStream.Position:= 0;
    kk := ReadInt; //fieldcount
    try
      for a := 0 To kk - 1 do
        begin
          //tx := AStream.ReadAnsiString;
          tx := ReadStr;
          ftype := ReadInt;
          len := ReadInt;
          req := ReadInt > 0;  // required field if boolean value > 0
          FieldDefs.Add(tx, TFieldType(fType), len, req);
        end;
      Open;  // Open - setup fields structure for memtable

      kk := ReadInt; // recordcount
      for a := 0 to kk-1 do
        begin
          Append;
          for b := 0 to FieldCount - 1 do
            begin
              cc := ReadInt;
              case cc of
                -maxint..-1: ReadBlob;
                0:           ; //No data - ignore
                1..1000:     ReadData; //simple type
                1001:        Fields[b].AsString :=  ReadStr;
              end; //case
            end;
          Post;
        end;
      First;
    finally
      EnableControls;
    end;
 // end;
end;

procedure TZAbstractMemTable.SaveToStream(AStream: TStream);
var bm: TBookMark; a, cc: Integer;
    tb: TBytes;
    ms: TMemoryStream;

  procedure WriteInt(ii: longint);
  begin
    AStream.WriteBuffer(ii, Sizeof(longint))
  end;

  procedure WriteStr(tx: string);
  begin
    cc := Length(tx); WriteInt(cc);
    AStream.WriteBuffer(Pointer(tx)^, cc);
  end;

  procedure WriteBlob;
  var ms: TStream;
  begin
    ms:= TMemoryStream.Create;
    (Fields[a] as TBlobField).SaveToStream(ms);
    cc := -ms.Size; // -ve to indicate BLOB type
    WriteInt(cc);
    if cc < 0 then
      begin
        ms.Position := 0;
        AStream.CopyFrom(ms, abs(cc));
      end;
    ms.Free;
  end;

  procedure WriteData;
  begin
    cc := Fields[a].DataSize;
    SetLength(tb, cc);
    Fields[a].GetData(Pointer(tb));
    WriteInt(cc);
    AStream.Writebuffer(Pointer(tb)^, cc);
  end;

begin
  CheckActive;
  bm := GetBookmark;
  AStream.Position:= 0;
  try
    DisableControls;

    try
      WriteInt(FieldDefs.Count);
      for a := 0 To FieldDefs.Count - 1 do
        begin
          WriteStr(FieldDefs[a].Name);
          WriteInt(Integer(FieldDefs[a].DataType));
          WriteInt(FieldDefs[a].Size);
          WriteInt(ord(FieldDefs[a].Required));
        end;
      First;
      WriteInt(RecordCount);
      while not Eof Do
        begin
          for a := 0 To FieldCount - 1 Do
            case Fields[a].DataType of
                ftString, ftMemo:
                    begin
                      cc := 1001;  WriteInt(cc); // 1001 indicate that string type
                      WriteStr(Fields[a].AsString);
                    end;
                ftBlob: WriteBlob;
                else WriteData
            end; //case
          Next;
        end;
    finally
      EnableControls;
    end;
  finally
    GotoBookmark(bm);
  end;

end;


procedure TZAbstractMemTable.LoadFromFile(Filename: TFilename);
var F1: TFileStream;
begin
  F1 := TFileStream.Create(Filename, fmOpenRead + fmShareCompat);
  try
    Self.LoadFromStream(F1);
  finally;
    F1.Free;
  end;
end;

procedure TZAbstractMemTable.SaveToFile(Filename: TFilename);
var F1: TFileStream;
begin
  F1 := TFileStream.Create(Filename, fmCreate);
  try
    Self.SaveToStream(F1);
  finally
    F1.Free;
  end;
end;