Export (0) Print
Expand All

UInt16.Parse Method (String, IFormatProvider)

Converts the string representation of a number in a specified culture-specific format to its 16-bit unsigned integer equivalent.

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

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

[CLSCompliantAttribute(false)]
public static ushort Parse(
	string s,
	IFormatProvider provider
)

Parameters

s
Type: System.String

A string that represents the number to convert.

provider
Type: System.IFormatProvider

An object that supplies culture-specific formatting information about s.

Return Value

Type: System.UInt16
A 16-bit unsigned integer equivalent to the number specified in s.

ExceptionCondition
ArgumentNullException

s is null.

FormatException

s is not in the correct format.

OverflowException

s represents a number less than UInt16.MinValue or greater than UInt16.MaxValue.

The s parameter contains a number of the form:

[ws][sign]digits[ws]

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

Element

Description

ws

Optional white space.

sign

An optional sign, or a negative sign if s represents the value zero.

digits

A sequence of digits ranging from 0 to 9.

The s parameter is interpreted using the NumberStyles.Integer style. In addition to the byte 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 instantiates a custom culture that uses two plus signs (++) as its positive sign. It then calls the Parse(String, IFormatProvider) method to parse an array of strings by using CultureInfo objects that represent both this custom culture and the invariant culture.

Imports System.Globalization

Module Example
   Public Sub Main()
      Dim values() As String = { " 214 ", "1,064", "(0)", "1241+", " + 214 ", " +214 ", "2153.0", "1e03", "1300.0e-2" }
      Dim whitespace As NumberStyles =  NumberStyles.AllowLeadingWhite Or NumberStyles.AllowTrailingWhite
      Dim styles() As NumberStyles = { NumberStyles.None, _
                                       whitespace, _
                                       NumberStyles.AllowLeadingSign Or NumberStyles.AllowTrailingSign Or whitespace, _
                                       NumberStyles.AllowThousands Or NumberStyles.AllowCurrencySymbol, _
                                       NumberStyles.AllowExponent Or NumberStyles.AllowDecimalPoint }

      ' Attempt to convert each number using each style combination. 
      For Each value As String In values
         Console.WriteLine("Attempting to convert '{0}':", value)
         For Each style As NumberStyles In styles
            Try 
               Dim number As UShort = UInt16.Parse(value, style)
               Console.WriteLine("   {0}: {1}", style, number)
            Catch e As FormatException
               Console.WriteLine("   {0}: Bad Format", style)
            End Try          
         Next
         Console.WriteLine()
      Next 
   End Sub 
End Module 
' The example displays the following output: 
'    Attempting to convert ' 214 ': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: 214 
'       Integer, AllowTrailingSign: 214 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: Bad Format 
'     
'    Attempting to convert '1,064': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: Bad Format 
'       AllowThousands, AllowCurrencySymbol: 1064 
'       AllowDecimalPoint, AllowExponent: Bad Format 
'     
'    Attempting to convert '(0)': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: Bad Format 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: Bad Format 
'     
'    Attempting to convert '1241+': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: 1241 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: Bad Format 
'     
'    Attempting to convert ' + 214 ': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: Bad Format 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: Bad Format 
'     
'    Attempting to convert ' +214 ': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: 214 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: Bad Format 
'     
'    Attempting to convert '2153.0': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: Bad Format 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: 2153 
'     
'    Attempting to convert '1e03': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: Bad Format 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: 1000 
'     
'    Attempting to convert '1300.0e-2': 
'       None: Bad Format 
'       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
'       Integer, AllowTrailingSign: Bad Format 
'       AllowThousands, AllowCurrencySymbol: Bad Format 
'       AllowDecimalPoint, AllowExponent: 13
using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      string[] values = { " 214 ", "1,064", "(0)", "1241+", " + 214 ", " +214 ", "2153.0", "1e03", "1300.0e-2" };
      NumberStyles whitespace =  NumberStyles.AllowLeadingWhite | NumberStyles.AllowTrailingWhite;
      NumberStyles[] styles = { NumberStyles.None, whitespace, 
                                NumberStyles.AllowLeadingSign | NumberStyles.AllowTrailingSign | whitespace, 
                                NumberStyles.AllowThousands | NumberStyles.AllowCurrencySymbol, 
                                NumberStyles.AllowExponent | NumberStyles.AllowDecimalPoint };

      // Attempt to convert each number using each style combination. 
      foreach (string value in values)
      {
         Console.WriteLine("Attempting to convert '{0}':", value);
         foreach (NumberStyles style in styles)
         {
            try {
               ushort number = UInt16.Parse(value, style);
               Console.WriteLine("   {0}: {1}", style, number);
            }   
            catch (FormatException) {
               Console.WriteLine("   {0}: Bad Format", style);
            }
         }
         Console.WriteLine();
      }
   }
}
// The example display the following output: 
//    Attempting to convert ' 214 ': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: 214 
//       Integer, AllowTrailingSign: 214 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: Bad Format 
//     
//    Attempting to convert '1,064': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: Bad Format 
//       AllowThousands, AllowCurrencySymbol: 1064 
//       AllowDecimalPoint, AllowExponent: Bad Format 
//     
//    Attempting to convert '(0)': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: Bad Format 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: Bad Format 
//     
//    Attempting to convert '1241+': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: 1241 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: Bad Format 
//     
//    Attempting to convert ' + 214 ': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: Bad Format 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: Bad Format 
//     
//    Attempting to convert ' +214 ': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: 214 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: Bad Format 
//     
//    Attempting to convert '2153.0': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: Bad Format 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: 2153 
//     
//    Attempting to convert '1e03': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: Bad Format 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: 1000 
//     
//    Attempting to convert '1300.0e-2': 
//       None: Bad Format 
//       AllowLeadingWhite, AllowTrailingWhite: Bad Format 
//       Integer, AllowTrailingSign: Bad Format 
//       AllowThousands, AllowCurrencySymbol: Bad Format 
//       AllowDecimalPoint, AllowExponent: 13
using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      // Define a custom culture that uses "++" as a positive sign. 
      CultureInfo ci = new CultureInfo("");
      ci.NumberFormat.PositiveSign = "++";
      // Create an array of cultures.
      CultureInfo[] cultures = { ci, CultureInfo.InvariantCulture };
      // Create an array of strings to parse. 
      string[] values = { "++1403", "-0", "+0", "+16034", 
                          Int16.MinValue.ToString(), "14.0", "18012" };
      // Parse the strings using each culture. 
      foreach (CultureInfo culture in cultures)
      {
         Console.WriteLine("Parsing with the '{0}' culture.", culture.Name);
         foreach (string value in values)
         {
            try {
               ushort number = UInt16.Parse(value, culture);
               Console.WriteLine("   Converted '{0}' to {1}.", value, number);
            }
            catch (FormatException) {
               Console.WriteLine("   The format of '{0}' is invalid.", value);
            }
            catch (OverflowException) {
               Console.WriteLine("   '{0}' is outside the range of a UInt16 value.", value);
            }               
         }
      }
   }
}
// The example displays the following output: 
//       Parsing with the  culture. 
//          Converted '++1403' to 1403. 
//          Converted '-0' to 0. 
//          The format of '+0' is invalid. 
//          The format of '+16034' is invalid. 
//          '-32768' is outside the range of a UInt16 value. 
//          The format of '14.0' is invalid. 
//          Converted '18012' to 18012. 
//       Parsing with the '' culture. 
//          The format of '++1403' is invalid. 
//          Converted '-0' to 0. 
//          Converted '+0' to 0. 
//          Converted '+16034' to 16034. 
//          '-32768' is outside the range of a UInt16 value. 
//          The format of '14.0' is invalid. 
//          Converted '18012' to 18012.

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

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

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

Show:
© 2014 Microsoft