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UInt64.MaxValue Field

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Represents the largest possible value of UInt64. This field is constant.

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

Syntax

'Declaration
Public Const MaxValue As ULong
public const ulong MaxValue

Remarks

The value of this constant is 18,446,744,073,709,551,615; that is, hexadecimal 0xFFFFFFFFFFFFFFFF.

Examples

The following example uses the MinValue and MaxValue fields to verify that a Double value is within the range of the UInt64 type before it performs a type conversion. This prevents an OverflowException at run time.

Dim decimalValue As Double = -1.5
Dim integerValue As ULong

' Discard fractional portion of Double value
Dim decimalInteger As Double = Math.Floor(decimalValue)

If decimalInteger < ULong.MaxValue AndAlso _
   decimalInteger > ULong.MinValue Then
   integerValue = CULng(decimalValue)
   outputBlock.Text += String.Format("Converted {0} to {1}.", decimalValue, integerValue) + vbCrLf
Else
   Dim rangeLimit As ULong
   Dim relationship As String

   If decimalInteger > ULong.MaxValue Then
      rangeLimit = ULong.MaxValue
      relationship = "greater"
   Else
      rangeLimit = ULong.MinValue
      relationship = "less"
   End If

   outputBlock.Text += String.Format("Conversion failure: {0} is {1} than {2}", _
                     decimalInteger, _
                     relationship, _
                     rangeLimit) + vbCrLf
End If
double decimalValue = -1.5;
ulong integerValue;

// Discard fractional portion of Double value
double decimalInteger = Math.Floor(decimalValue);

if (decimalInteger < ulong.MaxValue &&
    decimalInteger > ulong.MinValue)
{
   integerValue = (ulong)decimalValue;
   outputBlock.Text += String.Format("Converted {0} to {1}.", decimalValue, integerValue) + "\n";
}
else
{
   ulong rangeLimit;
   string relationship;

   if (decimalInteger > ulong.MaxValue)
   {
      rangeLimit = ulong.MaxValue;
      relationship = "greater";
   }
   else
   {
      rangeLimit = ulong.MinValue;
      relationship = "less";
   }

   outputBlock.Text += String.Format("Conversion failure: {0} is {1} than {2}.",
                     decimalInteger,
                     relationship,
                     rangeLimit) + "\n";
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.