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Int16.Parse Method (String, NumberStyles)

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

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

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

Parameters

s
Type: System.String

A string containing a number to convert.

style
Type: System.Globalization.NumberStyles

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

Return Value

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

ExceptionCondition
ArgumentNullException

s is Nothing.

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.

The style parameter defines the style elements (such as white space or a sign symbol) 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]

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, 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, the s parameter 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 without a prefix. For example, "9AF3" parses successfully, but "0x9AF3" does not. 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 s parameter is parsed using the formatting information in a NumberFormatInfo object that is initialized for the current system culture. For more information, see NumberFormatInfo.CurrentInfo. To parse s using the formatting information of a specific culture, call the Int16.Parse(String, NumberStyles, IFormatProvider) method.

The following example uses the Int16.Parse(String, NumberStyles) method to parse the string representations of Int16 values using the en-US culture.

Imports System.Globalization

Module ParseSample
   Public Sub Main()
      Dim value As String  
      Dim style As NumberStyles

      ' Parse a number with a thousands separator (throws an exception).
      value = "14,644"
      style = NumberStyles.None
      ParseToInt16(value, style)

      style = NumberStyles.AllowThousands
      ParseToInt16(value, style)

      ' Parse a number with a thousands separator and decimal point.
      value = "14,644.00"
      style = NumberStyles.AllowThousands Or NumberStyles.Integer Or _
              NumberStyles.AllowDecimalPoint
      ParseToInt16(value, style)

      ' Parse a number with a fractional component (throws an exception).
      value = "14,644.001"
      ParseToInt16(value, style)

      ' Parse a number in exponential notation.
      value = "145E02"
      style = style Or NumberStyles.AllowExponent
      ParseToInt16(value, style)

      ' Parse a number in exponential notation with a positive sign.
      value = "145E+02"
      ParseToInt16(value, style)

      ' Parse a number in exponential notation with a negative sign 
      ' (throws an exception).
      value = "145E-02"
      ParseToInt16(value, style)
   End Sub 

   Private Sub ParseToInt16(value As String, style As NumberStyles)
      Try 
         Dim number As Short = Int16.Parse(value, style)
         Console.WriteLine("Converted '{0}' to {1}.", value, number)
      Catch e As FormatException
         Console.WriteLine("Unable to parse '{0}' with style {1}.", value, _
                           style.ToString())
      Catch e As OverflowException
         Console.WriteLine("'{0}' is out of range of the Int16 type.", value)
      End Try 
   End Sub    
End Module 
' The example displays the following output to the console: 
'       Unable to parse '14,644' with style None. 
'       Converted '14,644' to 14644. 
'       Converted '14,644.00' to 14644. 
'       '14,644.001' is out of range of the Int16 type. 
'       Converted '145E02' to 14500. 
'       Converted '145E+02' to 14500. 
'       '145E-02' is out of range of the Int16 type.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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