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Decimal.Parse Method (String, IFormatProvider)

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Converts the string representation of a number to its Decimal equivalent using the specified culture-specific format information.

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

Syntax

'Declaration
Public Shared Function Parse ( _
    s As String, _
    provider As IFormatProvider _
) As Decimal

public static decimal Parse(
    string s,
    IFormatProvider provider
)

Parameters

  • s
    Type: System.String
    The string representation of the number to convert.

Return Value

Type: System.Decimal
The Decimal number equivalent to the number contained in s as specified by provider.

Exceptions

Exception Condition
ArgumentNullException

s is nulla null reference (Nothing in Visual Basic).
FormatException

s is not of the correct format
OverflowException

s represents a number less than MinValue or greater than MaxValue

Remarks

This overload of the Parse(String, IFormatProvider) method is commonly used to convert text that can be formatted in a variety of ways to a Decimal value. For example, it can be used to convert the text entered by a user into an HTML text box to a numeric value.

The s parameter contains a number of the form:

[ws][sign][digits,]digits[.fractional-digits][ws]

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

Element

Description

ws

Optional white space.

sign

An optional sign.

digits

A sequence of digits ranging from 0 to 9.

,

A culture-specific thousands separator symbol.

.

A culture-specific decimal point symbol.

fractional-digits

A sequence of digits ranging from 0 to 9.

The s parameter is interpreted using the NumberStyles.Number style. This means that white space and thousands separators are allowed but currency symbols are not. To explicitly define the elements (such as currency symbols, thousands separators, and white space) that can be present in s, use the Decimal.Parse(String, NumberStyles, IFormatProvider) method.

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 nulla null reference (Nothing in Visual Basic), the thread current culture is used.

A Decimal object has 29 digits of precision. If s represents a number that has more than 29 digits, but has a fractional part and is within the range of MaxValue and MinValue, the number is rounded, not truncated, to 29 digits using rounding to nearest.

If a separator is encountered in the s parameter during a parse operation, and the applicable currency or number decimal and group separators are the same, the parse operation assumes that the separator is a decimal separator rather than a group separator. For more information about separators, see CurrencyDecimalSeparator, NumberDecimalSeparator, CurrencyGroupSeparator, and NumberGroupSeparator.

Examples

The following example illustrates the use of the Parse(String, IFormatProvider) method to parse a string. The method first tries to parse the string using the current culture. If the parse operation fails, it tries to parse the string using a neutral culture. If this parse operation fails, it tries to parse the string using the invariant culture. Note that in a real application, the Decimal.TryParse(String, NumberStyles, IFormatProvider, Decimal%) method is best used for this purpose.

Public Function GetDecimal(value As String) As Decimal
   Dim culture As CultureInfo = Nothing
   Dim number As Decimal

   ' Throw exception if string is empty.
   If String.IsNullOrEmpty(value) Then _
      Throw New ArgumentNullException("The input string is invalid.")

   ' Determine if value can be parsed using current culture.
   Try
      culture = CultureInfo.CurrentCulture
      number = Decimal.Parse(value, culture)
      Return number
   Catch 
   End Try
   ' If Parse operation fails, see if there's a neutral culture.
   Try 
      culture = culture.Parent
      number = Decimal.Parse(value, culture)
      Return number
   Catch 
   End Try
   ' If there is no neutral culture or if parse operation fails, use
   ' the invariant culture.
   culture = CultureInfo.InvariantCulture
   Try 
      number = Decimal.Parse(value, culture)
      Return number
   ' All attempts to parse the string have failed; rethrow the exception.
   Catch e As FormatException
      Throw New FormatException(String.Format("Unable to parse '{0}'.", value), _ 
                                e)
   End Try
End Function

public static decimal GetDecimal(string value)
{
   decimal number;
   CultureInfo culture = null;

   // Return if string is empty
   if (String.IsNullOrEmpty(value))
      throw new ArgumentNullException("The input string is invalid.");

   // Determine if value can be parsed using current culture.
   try
   {
      culture = CultureInfo.CurrentCulture;
      number = decimal.Parse(value, culture);
      return number;
   }
   catch {}
   // If Parse operation fails, see if there's a neutral culture.
   try {
      culture = culture.Parent;
      number = decimal.Parse(value, culture);
      return number;
   }   
   catch {}
   // If there is no neutral culture or if parse operation fails, use
   // the invariant culture.
   culture = CultureInfo.InvariantCulture;
   try {
      number = decimal.Parse(value, culture);
      return number;
   }
   // All attempts to parse the string have failed; rethrow the exception.
   catch (FormatException e)
   {
      throw new FormatException(String.Format("Unable to parse '{0}'.", value), 
                                e);
   }
}

Version Information

Silverlight

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

Platforms

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