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SByte.Parse Method (String, NumberStyles)

Converts the string representation of a number in a specified style to its 8-bit signed integer equivalent.

This API is not CLS-compliant. The CLS-compliant alternative is Parse.

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

[CLSCompliantAttribute(false)]
public static sbyte Parse(
	string s,
	NumberStyles style
)

Parameters

s
Type: System.String

A string that contains a number to convert. The string is interpreted using the style specified by style.

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.SByte
An 8-bit signed integer that is equivalent to the number specified in s.

ExceptionCondition
ArgumentNullException

s is null.

FormatException

s is not in a format that is compliant with style.

OverflowException

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

-or-

s includes non-zero, fractional digits.

ArgumentException

style is not a NumberStyles value.

-or-

style is not a combination of AllowHexSpecifier and HexNumber values.

The style parameter defines the style elements (such as white space or the positive or negative 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[.fractional_digits][E[sign]exponential_digits][ws]

If style includes NumberStyles.AllowHexSpecifier, the s parameter may contain the following elements:

[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, and 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.CurrencyPositivePattern 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 decimal point symbol. The current culture's decimal point symbol can appear in s if style includes the NumberStyles.AllowDecimalPoint flag.

fractional_digits

One or more occurrences of the digit 0-9 if style includes the NumberStyles.AllowExponent flag, or one or more occurrences of the digit 0 if it does not. 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 (scientific) notation. The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.

exponential_digits

One or more occurrences of the digit 0-9. The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.

hexdigits

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

A string with decimal digits only (which corresponds to the NumberStyles.None style) always parses successfully. Most of the remaining NumberStyles members control elements that may be present, 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.

Non-composite NumberStyles values

Elements permitted in s in addition to digits

NumberStyles.None

Decimal digits only.

NumberStyles.AllowDecimalPoint

The decimal point (.) and fractional_digits elements. However, if style does not include the NumberStyles.AllowExponent flag, fractional_digits must consist of only one or more 0 digits; otherwise, an OverflowException is thrown.

NumberStyles.AllowExponent

The "e" or "E" character, which indicates exponential notation, along with exponential_digits.

NumberStyles.AllowLeadingWhite

The ws element at the beginning of s.

NumberStyles.AllowTrailingWhite

The ws element at the end of s.

NumberStyles.AllowLeadingSign

A positive sign before digits.

NumberStyles.AllowTrailingSign

A positive sign after digits.

NumberStyles.AllowParentheses

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

NumberStyles.AllowThousands

The group separator (,) element. Although the group separator can appear in s, it must be preceded by only one or more 0 digits.

NumberStyles.AllowCurrencySymbol

The currency ($) element.

If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value. The only other flags that can be combined with it are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. (The NumberStyles enumeration includes a composite number style, NumberStyles.HexNumber, that includes both white-space flags.)

NoteNote

If the s parameter is the string representation of a hexadecimal number, it cannot be preceded by any decoration (such as 0x or &h) that differentiates it as a hexadecimal number. This causes the parse operation to throw an exception.

If s represents a hexadecimal number, the Parse(String, NumberStyles) method interprets the high-order bit of the byte as a sign bit.

The s parameter is parsed by using the formatting information in a NumberFormatInfo object that is initialized for the current system culture. To use the formatting information of some other culture, call the Parse(String, NumberStyles, IFormatProvider) overload.

The following example parses string representations of SByte values with the Parse(String, NumberStyles) method. The current culture for the example is en-US.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      NumberStyles style;
      sbyte number;

      // Parse value with no styles allowed. 
      string[] values1 = { " 121 ", "121", "-121" };
      style = NumberStyles.None;
      Console.WriteLine("Styles: {0}", style.ToString());
      foreach (string value in values1)
      {
         try {
            number = SByte.Parse(value, style);
            Console.WriteLine("   Converted '{0}' to {1}.", value, number);
         }   
         catch (FormatException) {
            Console.WriteLine("   Unable to parse '{0}'.", value);
         }
      }
      Console.WriteLine();

      // Parse value with trailing sign.
      style = NumberStyles.Integer | NumberStyles.AllowTrailingSign;
      string[] values2 = { " 103+", " 103 +", "+103", "(103)", "   +103  " };
      Console.WriteLine("Styles: {0}", style.ToString());
      foreach (string value in values2)
      {
         try {
            number = SByte.Parse(value, style);
            Console.WriteLine("   Converted '{0}' to {1}.", value, number);
         }   
         catch (FormatException) {
            Console.WriteLine("   Unable to parse '{0}'.", value);
         }      
         catch (OverflowException) {
            Console.WriteLine("   '{0}' is out of range of the SByte type.", value);         
         }
      }      
      Console.WriteLine();
   }
}
// The example displays the following output: 
//       Styles: None 
//          Unable to parse ' 121 '. 
//          Converted '121' to 121. 
//          Unable to parse '-121'. 
//        
//       Styles: Integer, AllowTrailingSign 
//          Converted ' 103+' to 103. 
//          Converted ' 103 +' to 103. 
//          Converted '+103' to 103. 
//          Unable to parse '(103)'. 
//          Converted '   +103  ' to 103.

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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