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Decimal.TryParse Method (String, NumberStyles, IFormatProvider, Decimal%)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Converts the string representation of a number to its Decimal equivalent using the specified style and culture-specific format. A return value indicates whether the conversion succeeded or failed.

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

Syntax

'Declaration
Public Shared Function TryParse ( _
    s As String, _
    style As NumberStyles, _
    provider As IFormatProvider, _
    <OutAttribute> ByRef result As Decimal _
) As Boolean

public static bool TryParse(
    string s,
    NumberStyles style,
    IFormatProvider provider,
    out decimal result
)

Parameters

  • s
    Type: System.String
    The string representation of the number to convert.
  • result
    Type: System.Decimal%
    When this method returns, contains the Decimal number that is equivalent to the numeric value contained in s, if the conversion succeeded, or is zero if the conversion failed. The conversion fails if the s parameter is nulla null reference (Nothing in Visual Basic), is not in a format compliant with style, or represents a number less than MinValue or greater than MaxValue. This parameter is passed uninitialized.

Return Value

Type: System.Boolean
true if s was converted successfully; otherwise, false.

Exceptions

Exception Condition
ArgumentException

style is not a NumberStyles value.

-or-

style is the AllowHexSpecifier value.

Remarks

This overload differs from the Decimal.Parse(String, NumberStyles, IFormatProvider) method by returning a Boolean value that indicates whether the parse operation succeeded instead of returning the parsed numeric value. It eliminates the need to use exception handling to test for a FormatException in the event that s is invalid and cannot be successfully parsed.

The style parameter defines the allowable format of the s parameter for the parse operation to succeed. It must be a combination of bit flags from the NumberStyles enumeration. The following NumberStyles members are not supported:

Depending on the value of style, the s parameter may include the following elements:

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

Elements 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. 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.CurrencyNegativePattern or NumberFormatInfo.CurrencyPositivePattern properties of the NumberFormatInfo object returned by the IFormatProvider.GetFormat method of the provider parameter. The currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag.

sign

An optional sign.

digits

A sequence of digits ranging from 0 to 9.

.

A culture-specific decimal point symbol.

fractional-digits

A sequence of digits ranging from 0 to 9.

The style parameter specifies the permitted format of the s parameter, and can be one or more NumberStyles enumerated constants combined using a bitwise OR operation. If style is null, s is interpreted using the NumberStyles.Number style.

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 demonstrates the use of the TryParse(String, NumberStyles, IFormatProvider, Decimal%) method to parse the string representation of a number that has a particular style and is formatted using the conventions of a particular culture.

Dim value As String
Dim style As NumberStyles
Dim culture As CultureInfo
Dim number As Decimal

' Parse currency value using en-GB culture.
value = "£1,097.63"
style = NumberStyles.Number Or NumberStyles.AllowCurrencySymbol
culture = New CultureInfo("en-GB")
If Decimal.TryParse(value, style, culture, number) Then
   outputBlock.Text &= String.Format("Converted '{0}' to {1}.", value, number) & vbCrLf
Else
   outputBlock.Text &= String.Format("Unable to convert '{0}'.", value) & vbCrLf
End If
' Displays: 
'       Converted '£1,097.63' to 1097.63.

value = "1345,978"
style = NumberStyles.AllowDecimalPoint
culture = New CultureInfo("fr-FR")
If Decimal.TryParse(value, style, culture, number) Then
   outputBlock.Text &= String.Format("Converted '{0}' to {1}.", value, number) & vbCrLf
Else
   outputBlock.Text &= String.Format("Unable to convert '{0}'.", value) & vbCrLf
End If
' Displays:
'       Converted '1345,978' to 1345.978.

value = "1.345,978"
style = NumberStyles.AllowDecimalPoint Or NumberStyles.AllowThousands
culture = New CultureInfo("es-ES")
If Decimal.TryParse(value, style, culture, number) Then
   outputBlock.Text &= String.Format("Converted '{0}' to {1}.", value, number) & vbCrLf
Else
   outputBlock.Text &= String.Format("Unable to convert '{0}'.", value) & vbCrLf
End If
' Displays: 
'       Converted '1.345,978' to 1345.978.

value = "1 345,978"
If Decimal.TryParse(value, style, culture, number) Then
   outputBlock.Text &= String.Format("Converted '{0}' to {1}.", value, number) & vbCrLf
Else
   outputBlock.Text &= String.Format("Unable to convert '{0}'.", value) & vbCrLf
End If
' Displays:
'       Unable to convert '1 345,978'.

string value;
NumberStyles style;
CultureInfo culture;
decimal number;

// Parse currency value using en-GB culture.
value = "£1,097.63";
style = NumberStyles.Number | NumberStyles.AllowCurrencySymbol;
culture = new CultureInfo("en-GB");
if (Decimal.TryParse(value, style, culture, out number))
   outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) + "\n";
else
   outputBlock.Text += String.Format("Unable to convert '{0}'.", value) + "\n";
// Displays: 
//       Converted '£1,097.63' to 1097.63.

value = "1345,978";
style = NumberStyles.AllowDecimalPoint;
culture = new CultureInfo("fr-FR");
if (Decimal.TryParse(value, style, culture, out number))
   outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) + "\n";
else
   outputBlock.Text += String.Format("Unable to convert '{0}'.", value) + "\n";
// Displays:
//       Converted '1345,978' to 1345.978.

value = "1.345,978";
style = NumberStyles.AllowDecimalPoint | NumberStyles.AllowThousands;
culture = new CultureInfo("es-ES");
if (Decimal.TryParse(value, style, culture, out number))
   outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) + "\n";
else
   outputBlock.Text += String.Format("Unable to convert '{0}'.", value) + "\n";
// Displays: 
//       Converted '1.345,978' to 1345.978.

value = "1 345,978";
if (Decimal.TryParse(value, style, culture, out number))
   outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) + "\n";
else
   outputBlock.Text += String.Format("Unable to convert '{0}'.", value) + "\n";
// Displays:
//       Unable to convert '1 345,978'.

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.