Returns a 64-bit unsigned integer converted from eight bytes at a specified position in a byte array.
A 64-bit unsigned integer formed by the eight bytes beginning at startIndex.
The BitConverter.ToUInt64(Byte[], int) method converts the bytes from index startIndex to startIndex + 7 to a ulong value. The order of bytes in the array must reflect the endianness of the computer system's architecture; for more information, see the Remarks section of the BitConverter class topic.