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Decimal.Parse Method (String, NumberStyles, IFormatProvider)

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.

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

Syntax

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

public static decimal Parse(
    string s,
    NumberStyles style,
    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 style and provider.

Exceptions

Exception Condition
FormatException

s is not in the correct format.
OverflowException

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

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

style is not a NumberStyles value.

-or-

style is the AllowHexSpecifier value.

Remarks

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

$

A culture-specific currency symbol. Its position in the string is defined by the CurrencyNegativePattern and CurrencyPositivePattern properties 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.

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.

sign

An optional sign. The sign can appear at the beginning of s if style includes the NumberStyles.AllowLeadingSign flag, and it can appear 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

A sequence of digits ranging from 0 to 9.

,

A culture-specific thousands separator symbol. The thousands separator of the culture defined 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 defined by provider can appear in s if style includes the NumberStyles.AllowDecimalPoint flag.

fractional-digits

A sequence of digits ranging from 0 to 9. Fractional digits can appear in s only if style includes the NumberStyles.AllowDecimalPoint flag.

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.

A string with digits only (which corresponds to the None style) always parses successfully. The remaining NumberStyles members control elements that may be but are not required to be present in the input string. The following table indicates how individual NumberStyles members affect the elements that may be present in s.

NumberStyles value

Elements permitted in s in addition to digits

None

The digits element only.

AllowDecimalPoint

The . and fractional-digits elements.

AllowExponent

The s parameter can also use exponential notation. This flag supports values in the form digitsEdigits; additional flags are needed to successfully parse strings with elements such as positive or negative signs and decimal point symbols.

AllowLeadingWhite

The ws element at the beginning of s.

AllowTrailingWhite

The ws element at the end of s.

AllowLeadingSign

The sign element at the beginning of s.

AllowTrailingSign

The sign element at the end of s.

AllowParentheses

The sign element in the form of parentheses enclosing the numeric value.

AllowThousands

The , element.

AllowCurrencySymbol

The $ element.

Currency

All. The s parameter cannot represent a hexadecimal number or a number in exponential notation.

Float

The ws element at the beginning or end of s, sign at the beginning of s, and the .symbol. The s parameter can also use exponential notation.

Number

The ws, sign, ,, and . elements.

Any

All styles, except s cannot represent a hexadecimal number.

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 uses a variety of style and provider parameters to parse the string representations of Decimal values.

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

' Parse string using "." as the thousands separator 
' and " " as the decimal separator. 
value = "892 694,12"
style = NumberStyles.AllowDecimalPoint Or NumberStyles.AllowThousands
provider = New CultureInfo("fr-FR")

number = Decimal.Parse(value, style, provider)
outputBlock.Text &= String.Format("'{0}' converted to {1}.", value, number) & vbCrLf
' Displays: 
'    892 694,12' converted to 892694.12.

Try
   number = Decimal.Parse(value, style, CultureInfo.InvariantCulture)
   outputBlock.Text &= String.Format("'{0}' converted to {1}.", value, number) & vbCrLf
Catch e As FormatException
   outputBlock.Text &= String.Format("Unable to parse '{0}'.", value) & vbCrLf
End Try
' Displays: 
'    Unable to parse '892 694,12'.  

' Parse string using "$" as the currency symbol for en-GB and
' en-us cultures.
value = "$6,032.51"
style = NumberStyles.Number Or NumberStyles.AllowCurrencySymbol
provider = New CultureInfo("en-GB")

Try
   number = Decimal.Parse(value, style, provider)
   outputBlock.Text &= String.Format("'{0}' converted to {1}.", value, number) & vbCrLf
Catch e As FormatException
   outputBlock.Text &= String.Format("Unable to parse '{0}'.", value) & vbCrLf
End Try
' Displays: 
'    Unable to parse '$6,032.51'.

provider = New CultureInfo("en-US")
number = Decimal.Parse(value, style, provider)
outputBlock.Text &= String.Format("'{0}' converted to {1}.", value, number) & vbCrLf
' Displays: 
'    '$6,032.51' converted to 6032.51.

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

// Parse string using "." as the thousands separator 
// and " " as the decimal separator. 
value = "892 694,12";
style = NumberStyles.AllowDecimalPoint | NumberStyles.AllowThousands;
provider = new CultureInfo("fr-FR");

number = Decimal.Parse(value, style, provider);
outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) + "\n";
// Displays: 
//    892 694,12' converted to 892694.12.

try
{
   number = Decimal.Parse(value, style, CultureInfo.InvariantCulture);
   outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) + "\n";
}
catch (FormatException)
{
   outputBlock.Text += String.Format("Unable to parse '{0}'.", value) + "\n";
}
// Displays: 
//    Unable to parse '892 694,12'.  

// Parse string using "$" as the currency symbol for en-GB and  
// en-us cultures.
value = "$6,032.51";
style = NumberStyles.Number | NumberStyles.AllowCurrencySymbol;
provider = new CultureInfo("en-GB");

try
{
   number = Decimal.Parse(value, style, provider);
   outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) + "\n";
}
catch (FormatException)
{
   outputBlock.Text += String.Format("Unable to parse '{0}'.", value) + "\n";
}
// Displays: 
//    Unable to parse '$6,032.51'.

provider = new CultureInfo("en-US");
number = Decimal.Parse(value, style, provider);
outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) + "\n";
// Displays: 
//    '$6,032.51' converted to 6032.51.

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.