Welcome Sign in
Skip Navigation Links
Microsoft Developer Network
.NET Framework Class Library
UInt64 Structure

Updated: July 2008

Represents a 64-bit unsigned integer.

This API is not CLS-compliant. The CLS-compliant alternative is Decimal.

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

Visual Basic (Declaration)
<SerializableAttribute> _
<CLSCompliantAttribute(False)> _
<ComVisibleAttribute(True)> _
Public Structure UInt64 _
    Implements IComparable, IFormattable, IConvertible, IComparable(Of ULong),  _
    IEquatable(Of ULong)
Visual Basic (Usage)
Dim instance As UInt64
C#
[SerializableAttribute]
[CLSCompliantAttribute(false)]
[ComVisibleAttribute(true)]
public struct UInt64 : IComparable, IFormattable, 
    IConvertible, IComparable<ulong>, IEquatable<ulong>
Visual C++
[SerializableAttribute]
[CLSCompliantAttribute(false)]
[ComVisibleAttribute(true)]
public value class UInt64 : IComparable, 
    IFormattable, IConvertible, IComparable<unsigned long long>, IEquatable<unsigned long long>
J#
/** @attribute SerializableAttribute */ 
/** @attribute CLSCompliantAttribute(false) */
/** @attribute ComVisibleAttribute(true) */
public final class UInt64 extends ValueType implements IComparable, 
    IFormattable, IConvertible, IComparable<UInt64>, IEquatable<UInt64>
JScript
JScript supports the use of structures, but not the declaration of new ones.

The UInt64 value type represents unsigned integers with values ranging from 0 to 18,446,744,073,709,551,615.

Important Note:

   The UInt64 type is not CLS-compliant. The CLS-compliant alternative type is Decimal. Int64 can be used instead to replace a UInt64 value that ranges from zero to MaxValue. For more information about CLS compliance, see Common Language Specification.

UInt64 provides methods to compare instances of this type, convert the value of an instance to its string representation, and convert the string representation of a number to an instance of this type.

This type implements interfaces IComparable, IComparable<(Of <(T>)>), IFormattable, and IConvertible. Use the Convert class for conversions instead of this type's explicit interface member implementation of IConvertible.

All members of this type are thread safe. Members that appear to modify instance state actually return a new instance initialized with the new value. As with any other type, reading and writing to a shared variable that contains an instance of this type must be protected by a lock to guarantee thread safety.

Caution:

Assigning an instance of this type is not thread safe on all hardware platforms because the binary representation of that instance might be too large to assign in a single atomic operation.

Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 2.0, 1.0

Date

History

Reason

July 2008

Added note on CLS-compliant alternatives.

Content bug fix.

Page view tracker