Convert.ToUInt64 Method (String)

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

This API is not CLS-compliant. 

Namespace:  System
Assemblies:   System.Runtime.Extensions (in System.Runtime.Extensions.dll)
  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.

Using the ToInt64(String) method is equivalent to passing value to the Int64.Parse(String) method. value is interpreted by using the formatting conventions of the current thread culture.

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.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
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