Int32.Parse Method (String, NumberStyles, IFormatProvider) (System)

.NET Framework Class Library

Int32..::.Parse Method (String, NumberStyles, IFormatProvider)

Updated: July 2008

Converts the string representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent.

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

Syntax

Visual Basic (Declaration)

Public Shared Function Parse ( _
    s As String, _
    style As NumberStyles, _
    provider As IFormatProvider _
) As Integer

Visual Basic (Usage)

Dim s As String
Dim style As NumberStyles
Dim provider As IFormatProvider
Dim returnValue As Integer

returnValue = Integer.Parse(s, style, provider)

public static int Parse(
    string s,
    NumberStyles style,
    IFormatProvider provider
)

Visual C++

public:
static int Parse(
    String^ s, 
    NumberStyles style, 
    IFormatProvider^ provider
)

JScript

public static function Parse(
    s : String, 
    style : NumberStyles, 
    provider : IFormatProvider
) : int

Parameters

s: Type: System..::.String
A string containing a number to convert.

style: Type: System.Globalization..::.NumberStyles
A bitwise combination of enumeration values that indicates the style elements that can be present in s. A typical value to specify is Integer.

provider: Type: System..::.IFormatProvider
An IFormatProvider that supplies culture-specific information about the format of s.

Return Value

Type: System..::.Int32
A 32-bit signed integer equivalent to the number specified in s.

Exceptions

Exception	Condition
ArgumentNullException	s is nullNothingnullptra null reference (Nothing in Visual Basic).
ArgumentException	style is not a NumberStyles value. -or- style is not a combination of AllowHexSpecifier and HexNumber values.
FormatException	s is not in a format compliant with style.
OverflowException	s represents a number less than MinValue or greater than MaxValue. -or- s includes non-zero, fractional digits.

Remarks

The style parameter defines the style elements (such as white space or the positive sign) that are allowed in the s parameter for the parse operation to succeed. It must be a combination of bit flags from the NumberStyles enumeration. Depending on the value of style, the s parameter may include the following elements:

[ws][$][sign][digits,]digits[.fractional_digist][e[sign]exponential_digits][ws]

Or, if style includes AllowHexSpecifier:

[ws]hexdigits[ws]

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

Element	Description
ws	Optional white space. White space can appear at the beginning of s if style includes the NumberStyles..::.AllowLeadingWhite flag, and it can appear at the end of s if style includes the NumberStyles..::.AllowTrailingWhite flag.
$	A culture-specific currency symbol. Its position in the string is defined by the NumberFormatInfo..::.CurrencyPositivePattern property of the NumberFormatInfo object returned by the GetFormat method of the provider parameter. The currency symbol can appear in s if style includes the NumberStyles..::.AllowCurrencySymbol flag.
sign	An optional sign. The sign can appear at the beginning of s if style includes the NumberStyles..::.AllowLeadingSign flag or at the end of s if style includes the NumberStyles..::.AllowTrailingSign flag. Parentheses can be used in s to indicate a negative value if style includes the NumberStyles..::.AllowParentheses flag.
digits fractional_digits exponential_digits	A sequence of digits from 0 through 9. For fractional_digits, only the digit 0 is valid.
,	A culture-specific thousands separator symbol. The thousands separator of the culture specified by provider can appear in s if style includes the NumberStyles..::.AllowThousands flag.
.	A culture-specific decimal point symbol. The decimal point symbol of the culture specified by provider can appear in s if style includes the NumberStyles..::.AllowDecimalPoint flag. Only the digit 0 can appear as a fractional digit for the parse operation to succeed; if fractional_digits includes any other digit, an OverflowException is thrown.
e	The 'e' or 'E' character, which indicates that the value is represented in exponential notation. The s parameter can represent a number in exponential notation if style includes the NumberStyles..::.AllowExponent flag.
hexdigits	A sequence of hexadecimal digits from 0 through f, or 0 through F.

A string with decimal digits only (which corresponds to the NumberStyles..::.None style) always parses successfully if it is in the range of the Int32 type. Most of the remaining NumberStyles members control elements that may be but are not required to be present in this input string. The following table indicates how individual NumberStyles members affect the elements that may be present in s.

Non-composite NumberStyles values	Elements permitted in s in addition to digits
NumberStyles..::.None	Decimal digits only.
NumberStyles..::.AllowDecimalPoint	The decimal point ( . ) and fractional-digits elements. However, fractional-digits must consist of only one or more 0 digits or an OverflowException is thrown.
NumberStyles..::.AllowExponent	The s parameter can also use exponential notation. If s represents a number in exponential notation, it must represent an integer within the range of the Int32 data type without a non-zero, fractional component.
NumberStyles..::.AllowLeadingWhite	The ws element at the beginning of s.
NumberStyles..::.AllowTrailingWhite	The ws element at the end of s.
NumberStyles..::.AllowLeadingSign	A positive sign can appear before digits.
NumberStyles..::.AllowTrailingSign	A positive sign can appear after digits.
NumberStyles..::.AllowParentheses	The sign element in the form of parentheses enclosing the numeric value.
NumberStyles..::.AllowThousands	The thousands separator ( , ) element.
NumberStyles..::.AllowCurrencySymbol	The $ element.

If the NumberStyles..::.AllowHexSpecifier flag is used, s must be a hexadecimal value. The only other flags that can be present in style are NumberStyles..::.AllowLeadingWhite and NumberStyles..::.AllowTrailingWhite. (The NumberStyles enumeration has a composite number style, NumberStyles..::.HexNumber, that includes both white space flags.)

The provider parameter is an IFormatProvider implementation, such as a NumberFormatInfo or CultureInfo object. The provider parameter supplies culture-specific information used in parsing. If provider is nullNothingnullptra null reference (Nothing in Visual Basic), the NumberFormatInfo object for the current culture is used.

Examples

The following example uses a variety of style and provider parameters to parse the string representations of Int32 values. It also illustrates some of the different ways the same string can be interpreted depending on the culture whose formatting information is used for the parsing operation.

Visual Basic

Imports System.Globalization

Module ParseInt32
   Public Sub Main()
      Convert("12,000", NumberStyles.Float Or NumberStyles.AllowThousands, _
              New CultureInfo("en-GB"))      
      Convert("12,000", NumberStyles.Float Or NumberStyles.AllowThousands, _
              New CultureInfo("fr-FR"))
      Convert("12,000", NumberStyles.Float, New CultureInfo("en-US"))

      Convert("12 425,00", NumberStyles.Float Or NumberStyles.AllowThousands, _
              New CultureInfo("sv-SE")) 
      Convert("12,425.00", NumberStyles.Float Or NumberStyles.AllowThousands, _
              NumberFormatInfo.InvariantInfo) 
      Convert("631,900", NumberStyles.Integer Or NumberStyles.AllowDecimalPoint, _ 
              New CultureInfo("fr-FR"))
      Convert("631,900", NumberStyles.Integer Or NumberStyles.AllowDecimalPoint, _
              New CultureInfo("en-US"))
      Convert("631,900", NumberStyles.Integer Or NumberStyles.AllowThousands, _
              New CultureInfo("en-US"))
   End Sub

   Private Sub Convert(value As String, style As NumberStyles, _
                       provider As IFormatProvider)
      Try
         Dim number As Integer = Int32.Parse(value, style, provider)
         Console.WriteLine("Converted '{0}' to {1}.", value, number)
      Catch e As FormatException
         Console.WriteLine("Unable to convert '{0}'.", value)
      Catch e As OverflowException
         Console.WriteLine("'{0}' is out of range of the Int32 type.", value)   
      End Try
   End Sub                       
End Module
' This example displays the following output to the console:
'       Converted '12,000' to 12000.
'       Converted '12,000' to 12.
'       Unable to convert '12,000'.
'       Converted '12 425,00' to 12425.
'       Converted '12,425.00' to 12425.
'       '631,900' is out of range of the Int32 type.
'       Unable to convert '631,900'.
'       Converted '631,900' to 631900.

using System;
using System.Globalization;

public class ParseInt32
{
   public static void Main()
   {
      Convert("12,000", NumberStyles.Float | NumberStyles.AllowThousands, 
              new CultureInfo("en-GB"));
      Convert("12,000", NumberStyles.Float | NumberStyles.AllowThousands,
              new CultureInfo("fr-FR"));
      Convert("12,000", NumberStyles.Float, new CultureInfo("en-US"));

      Convert("12 425,00", NumberStyles.Float | NumberStyles.AllowThousands,
              new CultureInfo("sv-SE"));
      Convert("12,425.00", NumberStyles.Float | NumberStyles.AllowThousands,
              NumberFormatInfo.InvariantInfo);
      Convert("631,900", NumberStyles.Integer | NumberStyles.AllowDecimalPoint, 
              new CultureInfo("fr-FR"));
      Convert("631,900", NumberStyles.Integer | NumberStyles.AllowDecimalPoint,
              new CultureInfo("en-US"));
      Convert("631,900", NumberStyles.Integer | NumberStyles.AllowThousands,
              new CultureInfo("en-US"));
   }

   private static void Convert(string value, NumberStyles style, 
                               IFormatProvider provider)
   {
      try
      {
         int number = Int32.Parse(value, style, provider);
         Console.WriteLine("Converted '{0}' to {1}.", value, number);
      }
      catch (FormatException)
      {
         Console.WriteLine("Unable to convert '{0}'.", value);
      }   
      catch (OverflowException)
      {
         Console.WriteLine("'{0}' is out of range of the Int32 type.", value);   
      }
   }                               
}
// This example displays the following output to the console:
//       Converted '12,000' to 12000.
//       Converted '12,000' to 12.
//       Unable to convert '12,000'.
//       Converted '12 425,00' to 12425.
//       Converted '12,425.00' to 12425.
//       '631,900' is out of range of the Int32 type.
//       Unable to convert '631,900'.
//       Converted '631,900' to 631900.

Platforms

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.

Version Information