UInt64.Parse Method (String, IFormatProvider)

Converts the string representation of a number in a specified style and culture-specific format to its 64-bit unsigned integer equivalent.

This API is not CLS-compliant. The CLS-compliant alternative is Parse(String).

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

public static ulong Parse(
	string s,
	IFormatProvider provider


Type: System.String
A string representing the number to convert.
Type: System.IFormatProvider
An object that supplies culture-specific formatting information about s.

Return Value

Type: System.UInt64
A 64-bit unsigned integer equivalent to the number specified in s.


The s parameter is null.


The s parameter is not in the correct format.


The s parameter represents a number less than UInt64.MinValue or greater than UInt64.MaxValue.

The s parameter contains a number of the form:


Elements in square brackets ('[' and ']') are optional. The following table describes each element.




Optional white space.


An optional positive sign.


A sequence of digits ranging from 0 to 9.

The s parameter is interpreted using the NumberStyles.Integer style. In addition to the unsigned integer value's decimal digits, only leading and trailing spaces along with a leading sign is allowed. (If the negative sign is present, s must represent a value of zero, or the method throws an OverflowException.) To explicitly define the style elements together with the culture-specific formatting information that can be present in s, use the Parse(String, NumberStyles, IFormatProvider) method.

The provider parameter is an IFormatProvider implementation whose GetFormat method returns a NumberFormatInfo object that provides culture-specific information about the format of s. There are three ways to use the provider parameter to supply custom formatting information to the parse operation:

  • You can pass the actual NumberFormatInfo object that provides formatting information. (Its implementation of GetFormat simply returns itself.)

  • You can pass a CultureInfo object that specifies the culture whose formatting is to be used. Its NumberFormat property provides formatting information.

  • You can pass a custom IFormatProvider implementation. Its GetFormat method must instantiate and return the NumberFormatInfo object that provides formatting information.

If provider is null, the NumberFormatInfo for the current culture is used.

The following example attempts to parse an array of numeric strings by calling the Parse(String, IFormatProvider) method.

// Create an array of numeric strings.
string[] numericStrings = {"+106132", "-143105", "1,103,345.0", 
                           "6.1e12", "1.103.345,0", "+ 6034152", 
                           "  +139851752    "};
// Parse each string.
foreach (string numericString in numericStrings)
   // Parse the string.
   try {
      UInt64 number = UInt64.Parse(numericString, CultureInfo.InvariantCulture);
      outputBlock.Text += String.Format("Converted '{0}' to {1}.\n", 
                                        numericString, number);                     
   catch (FormatException) {
      outputBlock.Text += String.Format("'{0}' cannot be converted to an unsigned integer.\n", 
   catch (OverflowException) {
      outputBlock.Text += String.Format("{0} is outside the range of the UInt64 type.\n", 
// The example displays the following output:
//       Converted '+106132' to 106132.
//       -143105 is outside the range of the UInt64 type.
//       '1,103,345.0' cannot be converted to an unsigned integer.
//       '6.1e12' cannot be converted to an unsigned integer.
//       '1.103.345,0' cannot be converted to an unsigned integer.
//       '+ 6034152' cannot be converted to an unsigned integer.
//       Converted '  +139851752    ' to 139851752.


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

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

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