Convert.ToUInt64 Method (Int64)


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Converts the value of the specified 64-bit signed integer to an equivalent 64-bit unsigned integer.

This API is not CLS-compliant.

Namespace:   System
Assembly:  mscorlib (in mscorlib.dll)

public static ulong ToUInt64(
	long value


Type: System.Int64

The 64-bit signed integer to convert.

Return Value

Type: System.UInt64

A 64-bit unsigned integer that is equivalent to value.

Exception Condition

value is less than zero.

The following example attempts to convert each element in an array of long integers to an unsigned long integer.

long[] numbers = { Int64.MinValue, -19432, -18, 0, 121, 340, Int64.MaxValue };
ulong result;
foreach (long number in numbers)
   try {
      result = Convert.ToUInt64(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the UInt64 type.",
                        number.GetType().Name, number);
// The example displays the following output:
//    The Int64 value -9223372036854775808 is outside the range of the UInt64 type.
//    The Int64 value -19432 is outside the range of the UInt64 type.
//    The Int64 value -18 is outside the range of the UInt64 type.
//    Converted the Int64 value 0 to the UInt64 value 0.
//    Converted the Int64 value 121 to the UInt64 value 121.
//    Converted the Int64 value 340 to the UInt64 value 340.
//    Converted the Int64 value 9223372036854775807 to a UInt64 value 9223372036854775807.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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