BitConverter.ToUInt64 Method
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Returns a 64-bit unsigned integer converted from eight bytes at a specified position in a byte array.
Assembly: mscorlib (in mscorlib.dll)
'Declaration <CLSCompliantAttribute(False)> _ Public Shared Function ToUInt64 ( _ value As Byte(), _ startIndex As Integer _ ) As ULong
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 Nothing. |
| 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. Module Example Const formatter As String = "{0,5}{1,27}{2,24}" ' Convert eight Byte array elements to a UInt64 and display it. Sub BAToUInt64(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal bytes() As Byte, ByVal index As Integer) Dim value As UInt64 = BitConverter.ToUInt64(bytes, index) outputBlock.Text &= String.Format(formatter, index, _ BitConverter.ToString(bytes, index, 8), value) & vbCrLf End Sub ' Display a Byte array, using multiple lines if necessary. Sub WriteMultiLineByteArray(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal bytes() As Byte) Const rowSize As Integer = 20 Dim iter As Integer outputBlock.Text &= "initial Byte array" & vbCrLf outputBlock.Text &= "------------------" & vbCrLf For iter = 0 To bytes.Length - rowSize - 1 Step rowSize outputBlock.Text &= String.Format( _ BitConverter.ToString(bytes, iter, rowSize)) outputBlock.Text &= "-" & vbCrLf Next iter outputBlock.Text &= String.Format(BitConverter.ToString(bytes, iter)) & vbCrLf outputBlock.Text &= vbCrLf End Sub Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock) Dim byteArray As Byte() = { _ 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} outputBlock.Text &= String.Format( _ "This example of the BitConverter.ToUInt64( Byte( ), " & _ "Integer ) " & vbCrLf & "method generates the " & _ "following output. It converts elements " & vbCrLf & _ "of a Byte array to UInt64 values." & vbCrLf) & vbCrLf WriteMultiLineByteArray(outputBlock, byteArray) outputBlock.Text &= String.Format(formatter, "index", "array elements", _ "UInt64") & vbCrLf outputBlock.Text &= String.Format(formatter, "-----", "--------------", _ "------") & vbCrLf ' Convert Byte array elements to UInt64 values. BAToUInt64(outputBlock, byteArray, 3) BAToUInt64(outputBlock, byteArray, 0) BAToUInt64(outputBlock, byteArray, 21) BAToUInt64(outputBlock, byteArray, 7) BAToUInt64(outputBlock, byteArray, 29) BAToUInt64(outputBlock, byteArray, 13) BAToUInt64(outputBlock, byteArray, 35) BAToUInt64(outputBlock, byteArray, 44) BAToUInt64(outputBlock, byteArray, 43) End Sub End Module ' This example of the BitConverter.ToUInt64( Byte( ), Integer ) ' method generates the following output. It converts elements ' of a Byte array to UInt64 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 UInt64 ' ----- -------------- ------ ' 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