Delphi Binary Data

This post shows some code snippets for getting data from Delphi Byte arrays (TBytes) and TMemoryStream’s in and out of Chilkat.

First, here are some code snippets to convert from a TMemoryStream to a byte array, and back.

Delphi TBytes to TMemoryStream

var
  iStream: TMemoryStream;
  b: TBytes;
  OpFile: String;
  numBytes: Cardinal;

begin
  // Load a file into bytes
  OpFile := 'C:\qa_data\certs\cert_test123.cer';
  b := nil;
  numBytes := FileToBytes(OpFile, b);
  if (numBytes > 0) then
  begin
     // Byte array to TMemoryStream
     iStream := TMemoryStream.Create;
     iStream.Write(b[0], Length(b));
...

Delphi TMemoryStream to TBytes

var
  iStream: TMemoryStream;
  b: TBytes;
...
...
     // TMemoryStream to byte array.
     iStream.Seek(0, soBeginning);
     SetLength(b, iStream.Size);
     iStream.Read(Pointer(b)^, Length(b));
...

Load Delphi TBytes into Chilkat BinData

var
  b: TBytes;
  hData: HCkBinData;
  pointerToBytes: PByte;
...

begin
...
...
     hData := CkBinData_Create();
     pointerToBytes := PByte(b);

     CkBinData_AppendBinary2(hData,pointerToBytes,Length(b));

Write contents of Chilkat BinData to a TStream

var
  rawBytes: PByte;
  hData: HCkBinData;
  Stream: TMemoryStream;
  Writer: TBinaryWriter;
  i: Integer;
  numBytes: Integer;

begin
  hData:= CkBinData_Create();
  // Append 3 bytes (00, 01, and 02) to the CkBinData object.
  CkBinData_AppendEncoded(hData, '000102', 'hex');

  // Return pointer to raw bytes (internal data) as a System.PByte
  // Your application does not own the data.  If you do something
  // to the hData, such as append more data, or Clear(), then
  // your pointer to the bytes will become invalid.
  rawBytes := CkBinData_getBytesPtr(hData);
  numBytes := CkBinData_getNumBytes(hData);

  // Create a type of TStream and write the bytes to it.
  Stream := TMemoryStream.Create;
  try
    Writer := TBinaryWriter.Create(Stream);
    try
      for i := 0 to (numBytes - 1) do
      begin
        Writer.Write(rawBytes^);
        Inc(rawBytes);
      end;
    finally
      Writer.Free;
    end;
  finally
    Stream.Free;
  end;