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Int16.Parse Method (String, NumberStyles, IFormatProvider)

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

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

Syntax

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

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

Parameters

Return Value

Type: System.Int16
A 16-bit signed integer equivalent to the number specified in s.

Exceptions

Exception Condition
ArgumentNullException

s is nulla 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_digits][e[sign]digits][ws]

Or, if style includes AllowHexSpecifier:

[ws]hexdigits[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, or 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 and NumberFormatInfo.CurrencyNegativePattern property of the current culture. The current culture's 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, 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 from 0 through 9.

,

A culture-specific thousands separator symbol. The current culture's thousands separator symbol can appear in s if style includes the NumberStyles.AllowThousands flag.

.

A culture-specific decimal point symbol. The current culture's decimal point symbol can appear in s if style includes the NumberStyles.AllowDecimalPoint flag.

fractional_digits

A sequence of the 0 digit. Fractional digits can appear in s if style includes the NumberStyles.AllowDecimalPoint flag. If any digit other than 0 appears in fractional_digits, the method throws an OverflowException.

e

The 'e' or 'E' character, which indicates that s can be represented in exponential notation. The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag. However, s must represent a number in the range of the Int16 data type and cannot have a non-zero fractional component.

hexdigits

A sequence of hexadecimal digits from 0 through f, or 0 through F.

A string with digits only (which corresponds to the NumberStyles.None style) always parses successfully. 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 . 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.

NumberStyles.AllowLeadingWhite

The ws element at the beginning of s.

NumberStyles.AllowTrailingWhite

The ws element at the end of s.

NumberStyles.AllowLeadingSign

A sign can appear before digits.

NumberStyles.AllowTrailingSign

A sign can appear after digits.

NumberStyles.AllowParentheses

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

NumberStyles.AllowThousands

The , element.

NumberStyles.AllowCurrencySymbol

The $ element.

If the NumberStyles.AllowHexSpecifier flag is used, s must be the string representation of 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 whose GetFormat method obtains a NumberFormatInfo object. The NumberFormatInfo object provides culture-specific information about the format of s. If provider is nulla 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 Int16 values.

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

' Parse string using "." as the thousands separator 
' and " " as the decimal separator.
value = "19 694,00"
style = NumberStyles.AllowDecimalPoint Or NumberStyles.AllowThousands
provider = New CultureInfo("fr-FR")

number = Int16.Parse(value, style, provider)
outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) & vbCrLf
' Displays:
'    '19 694,00' converted to 19694.

Try
   number = Int16.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 '19 694,00'.

' Parse string using "$" as the currency symbol for en_GB and
' en-US cultures.
value = "$6,032.00"
style = NumberStyles.Number Or NumberStyles.AllowCurrencySymbol
provider = New CultureInfo("en-GB")

Try
   number = Int16.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 '$6,032.00'.

provider = New CultureInfo("en-US")
number = Int16.Parse(value, style, provider)
outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) & vbCrLf
' Displays:
'    '$6,032.00' converted to 6032.      

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

// Parse string using "." as the thousands separator 
// and " " as the decimal separator.
value = "19 694,00";
style = NumberStyles.AllowDecimalPoint | NumberStyles.AllowThousands;
provider = new CultureInfo("fr-FR");

number = Int16.Parse(value, style, provider);
outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) + "\n";
// Displays:
//    '19 694,00' converted to 19694.

try
{
   number = Int16.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 '19 694,00'.

// Parse string using "$" as the currency symbol for en_GB and
// en-US cultures.
value = "$6,032.00";
style = NumberStyles.Number | NumberStyles.AllowCurrencySymbol;
provider = new CultureInfo("en-GB");

try
{
   number = Int16.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 '$6,032.00'.

provider = new CultureInfo("en-US");
number = Int16.Parse(value, style, provider);
outputBlock.Text += String.Format("'{0}' converted to {1}.", value, number) + "\n";
// Displays:
//    '$6,032.00' converted to 6032.

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.