BitConverter.ToUInt64 Method
.NET Framework 4
Returns a 64-bit unsigned integer converted from eight bytes at a specified position in a byte array.
Assembly: mscorlib (in mscorlib.dll)
[CLSCompliantAttribute(false)] public static ulong ToUInt64( byte[] value, int startIndex )
Parameters
- value
- Type: System.Byte[]
An array of bytes.
- startIndex
- Type: System.Int32
The starting position within value.
Return Value
Type: System.UInt64A 64-bit unsigned integer formed by the eight bytes beginning at startIndex.
| Exception | Condition |
|---|---|
| ArgumentException |
startIndex is greater than or equal to the length of value minus 7, and is less than or equal to the length of value minus 1. |
| ArgumentNullException |
value is null. |
| ArgumentOutOfRangeException |
startIndex is less than zero or greater than the length of value minus 1. |
The following code example converts elements of Byte arrays to UInt64 values with the ToUInt64 method.
// Example of the BitConverter.ToUInt64 method. using System; class BytesToUInt64Demo { const string formatter = "{0,5}{1,27}{2,24}"; // Convert eight byte array elements to a ulong and display it. public static void BAToUInt64( byte[ ] bytes, int index ) { ulong value = BitConverter.ToUInt64( bytes, index ); Console.WriteLine( formatter, index, BitConverter.ToString( bytes, index, 8 ), value ); } // Display a byte array, using multiple lines if necessary. public static void WriteMultiLineByteArray( byte[ ] bytes ) { const int rowSize = 20; int iter; Console.WriteLine( "initial byte array" ); Console.WriteLine( "------------------" ); for( iter = 0; iter < bytes.Length - rowSize; iter += rowSize ) { Console.Write( BitConverter.ToString( bytes, iter, rowSize ) ); Console.WriteLine( "-" ); } Console.WriteLine( BitConverter.ToString( bytes, iter ) ); Console.WriteLine( ); } public static void Main( ) { byte[ ] byteArray = { 255, 255, 255, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 100, 167, 179, 182, 224, 13, 0, 202, 154, 59, 0, 0, 0, 0, 170, 170, 170, 170, 170, 170, 0, 0, 232, 137, 4, 35, 199, 138, 255, 255, 255, 255, 255, 255, 255, 255, 127 }; Console.WriteLine( "This example of the BitConverter.ToUInt64( byte[ ], " + "int ) \nmethod generates the following output. It " + "converts elements \nof a byte array to ulong values.\n" ); WriteMultiLineByteArray( byteArray ); Console.WriteLine( formatter, "index", "array elements", "ulong" ); Console.WriteLine( formatter, "-----", "--------------", "------" ); // Convert byte array elements to ulong values. BAToUInt64( byteArray, 3 ); BAToUInt64( byteArray, 0 ); BAToUInt64( byteArray, 21 ); BAToUInt64( byteArray, 7 ); BAToUInt64( byteArray, 29 ); BAToUInt64( byteArray, 13 ); BAToUInt64( byteArray, 35 ); BAToUInt64( byteArray, 44 ); BAToUInt64( byteArray, 43 ); } } /* This example of the BitConverter.ToUInt64( byte[ ], int ) method generates the following output. It converts elements of a byte array to ulong values. initial byte array ------------------ FF-FF-FF-00-00-00-00-00-00-00-00-01-00-00-00-64-A7-B3-B6-E0- 0D-00-CA-9A-3B-00-00-00-00-AA-AA-AA-AA-AA-AA-00-00-E8-89-04- 23-C7-8A-FF-FF-FF-FF-FF-FF-FF-FF-7F index array elements ulong ----- -------------- ------ 3 00-00-00-00-00-00-00-00 0 0 FF-FF-FF-00-00-00-00-00 16777215 21 00-CA-9A-3B-00-00-00-00 1000000000 7 00-00-00-00-01-00-00-00 4294967296 29 AA-AA-AA-AA-AA-AA-00-00 187649984473770 13 00-00-64-A7-B3-B6-E0-0D 1000000000000000000 35 00-00-E8-89-04-23-C7-8A 10000000000000000000 44 FF-FF-FF-FF-FF-FF-FF-7F 9223372036854775807 43 FF-FF-FF-FF-FF-FF-FF-FF 18446744073709551615 */
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
