BitConverter.ToUInt64 Method

Reference

Definition

Namespace:: System

Assembly:: System.Runtime.Extensions.dll

Assembly:: System.Runtime.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Overloads

ToUInt64(Byte[], Int32)	Returns a 64-bit unsigned integer converted from eight bytes at a specified position in a byte array.
ToUInt64(ReadOnlySpan<Byte>)	Converts bytes into an unsigned long.

ToUInt64(Byte[], Int32)

Source:: BitConverter.cs

Source:: BitConverter.cs

Source:: BitConverter.cs

Important

This API is not CLS-compliant.

Returns a 64-bit unsigned integer converted from eight bytes at a specified position in a byte array.

public:
 static System::UInt64 ToUInt64(cli::array <System::Byte> ^ value, int startIndex);

[System.CLSCompliant(false)]
public static ulong ToUInt64 (byte[] value, int startIndex);

[<System.CLSCompliant(false)>]
static member ToUInt64 : byte[] * int -> uint64

Public Shared Function ToUInt64 (value As Byte(), startIndex As Integer) As ULong

Parameters

value: Byte[]

An array of bytes that includes the eight bytes to convert.

startIndex: Int32

The starting position within value.

Returns

UInt64

A 64-bit unsigned integer formed by the eight bytes beginning at startIndex.

Attributes: CLSCompliantAttribute

Exceptions

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.

Examples

The following code example converts elements of Byte arrays to UInt64 values with the ToUInt64 method.

// Example of the BitConverter::ToUInt64 method.
using namespace System;

// Convert eight byte array elements to an unsigned __int64 value and 
// display it.
void BAToUInt64( array<unsigned char>^bytes, int index )
{
   unsigned __int64 value = BitConverter::ToUInt64( bytes, index );
   Console::WriteLine( "{0,5}{1,27}{2,24}", index, BitConverter::ToString( bytes, index, 8 ), value );
}


// Display a byte array, using multiple lines if necessary.
void WriteMultiLineByteArray( array<unsigned char>^bytes )
{
   const int rowSize = 20;
   int iter;
   Console::WriteLine( "initial unsigned char 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();
}

int main()
{
   array<unsigned char>^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( unsigned "
   "char[ ], int ) \nmethod generates the following output. It "
   "converts elements of a \nbyte array to unsigned __int64 "
   "values.\n" );
   WriteMultiLineByteArray( byteArray );
   Console::WriteLine( "{0,5}{1,27}{2,24}", "index", "array elements", "unsigned __int64" );
   Console::WriteLine( "{0,5}{1,27}{2,24}", "-----", "--------------", "----------------" );
   
   // Convert byte array elements to unsigned __int64 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( unsigned char[ ], int )
method generates the following output. It converts elements of a
byte array to unsigned __int64 values.

initial unsigned char 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        unsigned __int64
-----             --------------        ----------------
    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
*/

// 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
*/

open System

let print obj1 obj2 obj3 = printfn $"{obj1,5}{obj2,27}{obj3,24}"

// Convert eight byte array elements to a ulong and display it.
let BAToUInt64 bytes index =
    let value = BitConverter.ToUInt64(bytes, index)

    print index (BitConverter.ToString(bytes, index, 8)) value

// Display a byte array, using multiple lines if necessary.
let writeMultiLineByteArray (bytes: byte []) =
    let rowSize = 20

    printfn "initial byte array"
    printfn "------------------"

    let mutable iter = 0
    for i in 0 .. rowSize .. bytes.Length - rowSize - 1 do
        printfn $"{BitConverter.ToString(bytes, i, rowSize)}-"
        iter <- i

    printfn $"{BitConverter.ToString(bytes, iter + rowSize)}\n"

let byteArray =
    [| 255uy; 255uy; 255uy; 0uy; 0uy; 0uy; 0uy; 0uy; 0uy; 0uy
       0uy; 1uy; 0uy; 0uy; 0uy; 100uy; 167uy; 179uy; 182uy; 224uy
       13uy; 0uy; 202uy; 154uy; 59uy; 0uy; 0uy; 0uy; 0uy; 170uy
       170uy; 170uy; 170uy; 170uy; 170uy; 0uy; 0uy; 232uy; 137uy; 4uy
       35uy; 199uy; 138uy; 255uy; 255uy; 255uy; 255uy; 255uy; 255uy; 255uy
       255uy; 127uy |]

printfn "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 

print "index" "array elements" "ulong"
print "-----" "--------------" "------"

// 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

' Example of the BitConverter.ToUInt64 method.
Module BytesToUInt64Demo

    Const formatter As String = "{0,5}{1,27}{2,24}"
 
    ' Convert eight Byte array elements to a UInt64 and display it.
    Sub BAToUInt64( bytes( ) As Byte, index As Integer )

        Dim value As UInt64 = BitConverter.ToUInt64( bytes, index )

        Console.WriteLine( formatter, index, _
            BitConverter.ToString( bytes, index, 8 ), value )
    End Sub 

    ' Display a Byte array, using multiple lines if necessary.
    Sub WriteMultiLineByteArray( bytes( ) As Byte )
       
        Const rowSize As Integer = 20 
        Dim iter As Integer

        Console.WriteLine( "initial Byte array" )
        Console.WriteLine( "------------------" )

        For iter = 0 To bytes.Length - rowSize - 1 Step rowSize
            Console.Write( _
                BitConverter.ToString( bytes, iter, rowSize ) )
            Console.WriteLine( "-" )
        Next iter

        Console.WriteLine( BitConverter.ToString( bytes, iter ) )
        Console.WriteLine( )
    End Sub

    Sub Main( )
        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 }

        Console.WriteLine( _
            "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 )

        WriteMultiLineByteArray( byteArray )

        Console.WriteLine( formatter, "index", "array elements", _
            "UInt64" )
        Console.WriteLine( formatter, "-----", "--------------", _
            "------" )
          
        ' Convert Byte array elements to UInt64 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 )
    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

Remarks

The ToUInt64 method converts the bytes from index startIndex to startIndex + 7 to a UInt64 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.

Applies to

ToUInt64(ReadOnlySpan<Byte>)

Source:: BitConverter.cs

Source:: BitConverter.cs

Source:: BitConverter.cs

Important

This API is not CLS-compliant.

Converts bytes into an unsigned long.

public:
 static System::UInt64 ToUInt64(ReadOnlySpan<System::Byte> value);

[System.CLSCompliant(false)]
public static ulong ToUInt64 (ReadOnlySpan<byte> value);

[<System.CLSCompliant(false)>]
static member ToUInt64 : ReadOnlySpan<byte> -> uint64

Public Shared Function ToUInt64 (value As ReadOnlySpan(Of Byte)) As ULong

Parameters

value: ReadOnlySpan<Byte>

A read-only span containing the bytes to convert.

Returns

UInt64

A 64-bit unsigned integer representing the converted bytes.

Attributes: CLSCompliantAttribute

Exceptions

ArgumentOutOfRangeException

The length of value is less than 8.

Applies to

Share via

BitConverter.ToUInt64 Method

Definition

Overloads

ToUInt64(Byte[], Int32)

Parameters

Returns

Exceptions

Examples

Remarks

See also

Applies to

ToUInt64(ReadOnlySpan<Byte>)

Parameters

Returns

Exceptions

Applies to

Additional resources