// Assume that pdblDoubles is your array of doubles.
double [] pdblDoubles = {-10.2D};
byte[] pbytBytes = new byte[Buffer.ByteLength(pdblDoubles)];
// Now copy the bytes from the double array to the byte array.
Buffer.BlockCopy(pdblDoubles, 0, pbytBytes, 0, pbytBytes.Length);
-- 07/03/2009 18:47:41: post edited by sergey.