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Convert.ToUInt64 Method (String)

Updated: May 2009

Converts the specified string representation of a number to an equivalent 64-bit unsigned integer.

This API is not CLS-compliant. 

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

[CLSCompliantAttribute(false)]
public static ulong ToUInt64(
	string value
)

Parameters

value
Type: System.String

A string that contains the number to convert.

Return Value

Type: System.UInt64
A 64-bit signed integer that is equivalent to the number in value, or 0 (zero) if value is null.

ExceptionCondition
FormatException

value does not consist of an optional sign followed by a sequence of digits (0 through 9).

OverflowException

value represents a number that is less than UInt64.MinValue or greater than UInt64.MaxValue.

The return value is the result of invoking the UInt64.Parse method on value.

If you prefer not to handle an exception if the conversion fails, you can call the UInt64.TryParse method instead. It returns a Boolean value that indicates whether the conversion succeeded or failed.

The following example interprets the elements of a string array as numeric strings and attempts to convert them to unsigned long integers.

string[] values = { "One", "1.34e28", "-26.87", "-18", "-6.00",
                    " 0", "137", "1601.9", Int32.MaxValue.ToString() };
ulong result;

foreach (string value in values)
{
   try {
      result = Convert.ToUInt64(value);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        value.GetType().Name, value, result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the UInt64 type.", value);
   }   
   catch (FormatException) {
      Console.WriteLine("The {0} value '{1}' is not in a recognizable format.",
                        value.GetType().Name, value);
   }   
}                                 
// The example displays the following output: 
//    The String value 'One' is not in a recognizable format. 
//    The String value '1.34e28' is not in a recognizable format. 
//    The String value '-26.87' is not in a recognizable format. 
//    -18 is outside the range of the UInt64 type. 
//    The String value '-6.00' is not in a recognizable format. 
//    Converted the String value ' 0' to the UInt64 value 0. 
//    Converted the String value '137' to the UInt64 value 137. 
//    The String value '1601.9' is not in a recognizable format. 
//    Converted the String value '2147483647' to the UInt64 value 2147483647.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, 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, Zune

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: 3.0, 2.0, 1.0

Date

History

Reason

May 2009

Expanded the Remarks section.

Customer feedback.

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