使用流和动态数组读写文件

var

FileBuf:Array of Byte;//[0..4194304]

procedure TForm1.ReadWriteFile(SrcFile, DescFile: String);
var
MyFile:TMemoryStream;
iLen:Int64;
begin
iLen:=0;
try
MyFile:=TMemoryStream.Create;
MyFile.LoadFromFile(SrcFile);
iLen:=MyFile.Size;
SetLength(FileBuf,iLen);
MyFile.ReadBuffer(FileBuf[0],iLen);
finally
FreeAndNil(MyFile);
end;

try
MyFile:=TMemoryStream.Create;
MyFile.Seek(0,soFromBeginning);
MyFile.WriteBuffer(FileBuf[0],iLen);
MyFile.SaveToFile(DescFile);
finally
FreeAndNil(MyFile);
end;
end;