Seek location for a pattern bytes in memorystream

How can I seek a the location for a pattern bytes match in memorystream object ? Let say this is the bytes store in my memorystream object is like this :- 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0xFF 0xFF 0x01 0x02 0x05 0x12 0xFF 0xFF so right now i want to find out the first location in my stream which the pattern watch with this pattern of bytes 0xFF 0xFF... Can someone help me regarding this problem ?, thank you