文件和Variant的转换

function FileToVariant(FileName: String): OleVariant; 
var 
  AStream: TFileStream; 
  MyBuffer: Pointer; 
begin 
  AStream:=TFileStream.create(FileName,fmOpenRead); 
  try 
    aStream.Seek(0, soFromBeginning); 
    Result:=VarArraycreate([0, AStream.size-1], VarByte); 
    MyBuffer:=VarArrayLock(Result); 
    AStream.ReadBuffer(MyBuffer^, AStream.Size); 
    VarArrayUnlock(Result); 
  finally 
    AStream.Free; 
  end; 
end;

procedure VariantToFile(FileName: String; var AVariant: OleVariant); 
var 
  AStream: TFileStream; 
  MyBuffer: Pointer; 
  Size: Integer; 
begin 
  AStream:=TFileStream.create(FileName,fmCreate); 
  try 
    aStream.Seek(0, soFromBeginning); 
    Size:=VarArrayHighBound(AVariant,1)+VarArrayLowBound(AVariant,1)+1; 
    MyBuffer:=VarArrayLock(AVariant); 
    AStream.WriteBuffer(MyBuffer^, Size); 
    VarArrayUnlock(AVariant); 
  finally 
    AStream.Free; 
  end; 
end;