SByte.Parse Method (System) (original) (raw)

Source:

SByte.cs

Source:

SByte.cs

Source:

SByte.cs

Source:

SByte.cs

Converts the string representation of a number that is in a specified style and culture-specific format to its 8-bit signed equivalent.

public:
 static System::SByte Parse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider);

public:
 static System::SByte Parse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider) = System::Numerics::INumberBase<System::SByte>::Parse;

[System.CLSCompliant(false)]
public static sbyte Parse(string s, System.Globalization.NumberStyles style, IFormatProvider provider);

public static sbyte Parse(string s, System.Globalization.NumberStyles style, IFormatProvider? provider);

[System.CLSCompliant(false)]
public static sbyte Parse(string s, System.Globalization.NumberStyles style, IFormatProvider? provider);

[<System.CLSCompliant(false)>]
static member Parse : string * System.Globalization.NumberStyles * IFormatProvider -> sbyte

static member Parse : string * System.Globalization.NumberStyles * IFormatProvider -> sbyte

Public Shared Function Parse (s As String, style As NumberStyles, provider As IFormatProvider) As SByte

Parameters

s

String

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

style

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 Integer.

provider

IFormatProvider

An object that supplies culture-specific formatting information about s. If provider is null, the thread current culture is used.

Returns

An 8-bit signed byte value that is equivalent to the number specified in the s parameter.

Implements

Attributes

Exceptions

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

Examples

The following example illustrates the use of the Parse(String, NumberStyles, IFormatProvider) method to convert various string representations of numbers to signed integer values.

using System;
using System.Globalization;

public class SByteConversion
{
   NumberFormatInfo provider = NumberFormatInfo.CurrentInfo;

   public static void Main()
   {
      string stringValue;
      NumberStyles style;

      stringValue = "   123   ";
      style = NumberStyles.None;     
      CallParseOperation(stringValue, style);
      
      stringValue = "000,000,123";
      style = NumberStyles.Integer | NumberStyles.AllowThousands;
      CallParseOperation(stringValue, style);
      
      stringValue = "-100";
      style = NumberStyles.AllowLeadingSign;
      CallParseOperation(stringValue, style);
      
      stringValue = "100-";
      style = NumberStyles.AllowLeadingSign;
      CallParseOperation(stringValue, style);
      
      stringValue = "100-";
      style = NumberStyles.AllowTrailingSign;
      CallParseOperation(stringValue, style);
      
      stringValue = "$100";
      style = NumberStyles.AllowCurrencySymbol;
      CallParseOperation(stringValue, style);
      
      style = NumberStyles.Integer;
      CallParseOperation(stringValue, style);
      
      style = NumberStyles.AllowDecimalPoint;
      CallParseOperation("100.0", style);
      
      stringValue = "1e02";
      style = NumberStyles.AllowExponent;
      CallParseOperation(stringValue, style);
      
      stringValue = "(100)";
      style = NumberStyles.AllowParentheses;
      CallParseOperation(stringValue, style);
   }
   
   private static void CallParseOperation(string stringValue, 
                                          NumberStyles style)
   {                                          
      sbyte number;
      
      if (stringValue == null)
         Console.WriteLine("Cannot parse a null string...");
         
      try
      {
         number = sbyte.Parse(stringValue, style);
         Console.WriteLine("SByte.Parse('{0}', {1})) = {2}", 
                           stringValue, style, number);   
      }
      catch (FormatException)
      {
         Console.WriteLine("'{0}' and {1} throw a FormatException", 
                           stringValue, style);   
      }      
      catch (OverflowException)
      {
         Console.WriteLine("'{0}' is outside the range of a signed byte",
                           stringValue);
      }
   }
}
// The example displays the following information to the console:
//       '   123   ' and None throw a FormatException
//       SByte.Parse('000,000,123', Integer, AllowThousands)) = 123
//       SByte.Parse('-100', AllowLeadingSign)) = -100
//       '100-' and AllowLeadingSign throw a FormatException
//       SByte.Parse('100-', AllowTrailingSign)) = -100
//       SByte.Parse('$100', AllowCurrencySymbol)) = 100
//       '$100' and Integer throw a FormatException
//       SByte.Parse('100.0', AllowDecimalPoint)) = 100
//       SByte.Parse('1e02', AllowExponent)) = 100
//       SByte.Parse('(100)', AllowParentheses)) = -100

open System
open System.Globalization

let provider = NumberFormatInfo.CurrentInfo
   
let callParseOperation stringValue (style: NumberStyles) =
    if stringValue = null then
        printfn "Cannot parse a null string..."
    else
        try
            let number = SByte.Parse(stringValue, style)
            printfn $"SByte.Parse('{stringValue}', {style})) = {number}" 
        with
        | :? FormatException ->
            printfn $"'{stringValue}' and {style} throw a FormatException"
        | :? OverflowException ->
            printfn $"'{stringValue}' is outside the range of a signed byte"

[<EntryPoint>]
let main _ =
    let stringValue = "   123   "
    let style = NumberStyles.None     
    callParseOperation stringValue style
    
    let stringValue = "000,000,123"
    let style = NumberStyles.Integer ||| NumberStyles.AllowThousands
    callParseOperation stringValue style
    
    let stringValue = "-100"
    let style = NumberStyles.AllowLeadingSign
    callParseOperation stringValue style
    
    let stringValue = "100-"
    let style = NumberStyles.AllowLeadingSign
    callParseOperation stringValue style
    
    let stringValue = "100-"
    let style = NumberStyles.AllowTrailingSign
    callParseOperation stringValue style
    
    let stringValue = "$100"
    let style = NumberStyles.AllowCurrencySymbol
    callParseOperation stringValue style
    
    let style = NumberStyles.Integer
    callParseOperation stringValue style
    
    let style = NumberStyles.AllowDecimalPoint
    callParseOperation "100.0" style
    
    let stringValue = "1e02"
    let style = NumberStyles.AllowExponent
    callParseOperation stringValue style
    
    let stringValue = "(100)"
    let style = NumberStyles.AllowParentheses
    callParseOperation stringValue style
    0

// The example displays the following information to the console:
//       '   123   ' and None throw a FormatException
//       SByte.Parse('000,000,123', Integer, AllowThousands)) = 123
//       SByte.Parse('-100', AllowLeadingSign)) = -100
//       '100-' and AllowLeadingSign throw a FormatException
//       SByte.Parse('100-', AllowTrailingSign)) = -100
//       SByte.Parse('$100', AllowCurrencySymbol)) = 100
//       '$100' and Integer throw a FormatException
//       SByte.Parse('100.0', AllowDecimalPoint)) = 100
//       SByte.Parse('1e02', AllowExponent)) = 100
//       SByte.Parse('(100)', AllowParentheses)) = -100

Imports System.Globalization

Module modMain
   Public Sub Main()
      Dim byteString As String 
      
      byteString = " 123"
      ParseString(byteString, NumberStyles.None)
      ParseString(byteString, NumberStyles.Integer)
      
      byteString = "3A"
      ParseString(byteString, NumberStyles.AllowHexSpecifier) 
      
      byteString = "21"
      ParseString(byteString, NumberStyles.Integer)
      ParseString(byteString, NumberStyles.AllowHexSpecifier)
      
      byteString = "-22"
      ParseString(byteString, NumberStyles.Integer)
      ParseString(byteString, NumberStyles.AllowParentheses)
      
      byteString = "(45)"
      ParseString(byteString, NumberStyles.AllowParentheses)
     
      byteString = "000,000,056"
      ParseString(byteString, NumberStyles.Integer)
      ParseString(byteString, NumberStyles.Integer Or NumberStyles.AllowThousands)
   End Sub
   
   Private Sub ParseString(value As String, style As NumberStyles)
      Dim number As SByte
      
      If value Is Nothing Then Console.WriteLine("Cannot parse a null string...") 
      
      Try
         number = SByte.Parse(value, style, NumberFormatInfo.CurrentInfo)
         Console.WriteLine("SByte.Parse('{0}', {1}) = {2}", value, style, number)   
      Catch e As FormatException
         Console.WriteLine("'{0}' and {1} throw a FormatException", value, style)   
      Catch e As OverflowException
         Console.WriteLine("'{0}' is outside the range of a signed byte",
                           value)
      End Try     
   End Sub
End Module
' The example displays the following information to the console:
'       ' 123' and None throw a FormatException
'       SByte.Parse(" 123", Integer)) = 123
'       SByte.Parse("3A", AllowHexSpecifier)) = 58
'       SByte.Parse("21", Integer)) = 21
'       SByte.Parse("21", AllowHexSpecifier)) = 33
'       SByte.Parse("-22", Integer)) = -22
'       '-22' and AllowParentheses throw a FormatException
'       SByte.Parse("(45)", AllowParentheses)) = -45
'       '000,000,056' and Integer throw a FormatException
'       SByte.Parse("000,000,056", Integer, AllowThousands)) = 56

Remarks

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 AllowHexSpecifier, the s parameter may include the following elements:

[_ws_]_hexdigits_[_ws_]

Elements in square brackets ([ and ]) are optional. The following table describes each element.

Note

Any terminating NUL (U+0000) characters in s are ignored by the parsing operation, regardless of the value of the style argument.

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 this input string. The following table indicates how individual NumberStyles members affect the elements that may be present in s.

If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value. Valid hexadecimal digits are 0-9, a-f, and A-F. 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.)

Note

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 provider parameter is an IFormatProvider implementation whose GetFormat method returns a NumberFormatInfo object that provides culture-specific information about the format of s. There are three ways to use the provider parameter to supply custom formatting information to the parse operation:

• You can pass the actual NumberFormatInfo object that provides formatting information. (Its implementation of GetFormat simply returns itself.)
• You can pass a CultureInfo object that specifies the culture whose formatting is to be used. Its NumberFormat property provides formatting information.
• You can pass a custom IFormatProvider implementation. Its GetFormat method must instantiate and return the NumberFormatInfo object that provides formatting information.

If provider is null, the NumberFormatInfo object for the current culture is used.

Applies to