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Convert.ToSByte Method (String, IFormatProvider)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Converts the specified String representation of a number to an equivalent 8-bit signed integer using specified culture-specific formatting information.

This API is not CLS-compliant. 

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

Syntax

'Declaration
<CLSCompliantAttribute(False)> _
Public Shared Function ToSByte ( _
    value As String, _
    provider As IFormatProvider _
) As SByte
[CLSCompliantAttribute(false)]
public static sbyte ToSByte(
    string value,
    IFormatProvider provider
)

Parameters

Return Value

Type: System.SByte
An 8-bit signed integer equivalent to the value of value.

Exceptions

Exception Condition
ArgumentNullException

value is nulla null reference (Nothing in Visual Basic).

FormatException

value does not consist of an optional sign followed by a sequence of digits (zero through nine).

OverflowException

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

Remarks

provider is an IFormatProvider instance that obtains a NumberFormatInfo object. The NumberFormatInfo object provides culture-specific information about the format of value. If provider is nulla null reference (Nothing in Visual Basic), the NumberFormatInfo for the current culture is used.

If you prefer not to handle an exception if the conversion fails, you can call the SByte.TryParse method instead. It returns a Boolean value that indicates whether the conversion succeeded or failed.

Examples

The following code example converts String representations of SByte (signed byte) values with the ToSByte method, using an IFormatProvider object.

' Example of the Convert.ToSByte( String ) and 
' Convert.ToSByte( String, IFormatProvider ) methods.
Imports System.Globalization

Module Example

   Dim format As String = "{0,-20}{1,-20}{2}"

   ' Get the exception type name; remove the namespace prefix.
   Function GetExceptionType(ByVal ex As Exception) As String

      Dim exceptionType As String = ex.GetType().ToString()
      Return exceptionType.Substring( _
          exceptionType.LastIndexOf("."c) + 1)
   End Function

   Sub ConvertToSByte(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal numericStr As String, _
       ByVal provider As IFormatProvider)

      Dim defaultValue As Object
      Dim providerValue As Object

      ' Convert numericStr to SByte without a format provider.
      Try
         defaultValue = Convert.ToSByte(numericStr)
      Catch ex As Exception
         defaultValue = GetExceptionType(ex)
      End Try

      ' Convert numericStr to SByte with a format provider.
      Try
         providerValue = Convert.ToSByte(numericStr, provider)
      Catch ex As Exception
         providerValue = GetExceptionType(ex)
      End Try

      outputBlock.Text &= String.Format(format, numericStr, _
          defaultValue, providerValue) & vbCrLf
   End Sub

   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

      ' Create a NumberFormatInfo object and set several of its
      ' properties that apply to numbers.
      Dim provider As NumberFormatInfo = New NumberFormatInfo()

      ' These properties affect the conversion.
      provider.NegativeSign = "neg "
      provider.PositiveSign = "pos "

      ' These properties do not affect the conversion.
      ' The input string cannot have decimal and group separators.
      provider.NumberDecimalSeparator = "."
      provider.NumberNegativePattern = 0

      outputBlock.Text &= String.Format("This example of" & vbCrLf & _
          "  Convert.ToSByte( String ) and " & vbCrLf & _
          "  Convert.ToSByte( String, IFormatProvider ) " & _
          vbCrLf & "generates the following output. It " & _
          "converts several strings to " & vbCrLf & "SByte " & _
          "values, using default formatting " & _
          "or a NumberFormatInfo object." & vbCrLf) & vbCrLf
      outputBlock.Text &= String.Format(format, "String to convert", _
          "Default/exception", "Provider/exception") & vbCrLf
      outputBlock.Text &= String.Format(format, "-----------------", _
          "-----------------", "------------------") & vbCrLf

      ' Convert strings, with and without an IFormatProvider.
      ConvertToSByte(outputBlock, "123", provider)
      ConvertToSByte(outputBlock, "+123", provider)
      ConvertToSByte(outputBlock, "pos 123", provider)
      ConvertToSByte(outputBlock, "-123", provider)
      ConvertToSByte(outputBlock, "neg 123", provider)
      ConvertToSByte(outputBlock, "123.", provider)
      ConvertToSByte(outputBlock, "(123)", provider)
      ConvertToSByte(outputBlock, "128", provider)
      ConvertToSByte(outputBlock, "-129", provider)
   End Sub
End Module

' This example of
'   Convert.ToSByte( String ) and
'   Convert.ToSByte( String, IFormatProvider )
' generates the following output. It converts several strings to
' SByte values, using default formatting or a NumberFormatInfo object.
' 
' String to convert   Default/exception   Provider/exception
' -----------------   -----------------   ------------------
' 123                 123                 123
' +123                123                 FormatException
' pos 123             FormatException     123
' -123                -123                FormatException
' neg 123             FormatException     -123
' 123.                FormatException     FormatException
' (123)               FormatException     FormatException
' 128                 OverflowException   OverflowException
' -129                OverflowException   FormatException
// Example of the Convert.ToSByte( string ) and 
// Convert.ToSByte( string, IFormatProvider ) methods.
using System;
using System.Globalization;

class Example
{
   static string format = "{0,-20}{1,-20}{2}";

   // Get the exception type name; remove the namespace prefix.
   static string GetExceptionType(Exception ex)
   {
      string exceptionType = ex.GetType().ToString();
      return exceptionType.Substring(
          exceptionType.LastIndexOf('.') + 1);
   }

   static void ConvertToSByte(System.Windows.Controls.TextBlock outputBlock, string numericStr,
       IFormatProvider provider)
   {
      object defaultValue;
      object providerValue;

      // Convert numericStr to SByte without a format provider.
      try
      {
         defaultValue = Convert.ToSByte(numericStr);
      }
      catch (Exception ex)
      {
         defaultValue = GetExceptionType(ex);
      }

      // Convert numericStr to SByte with a format provider.
      try
      {
         providerValue = Convert.ToSByte(numericStr, provider);
      }
      catch (Exception ex)
      {
         providerValue = GetExceptionType(ex);
      }

      outputBlock.Text += String.Format(format, numericStr,
          defaultValue, providerValue) + "\n";
   }

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      // Create a NumberFormatInfo object and set several of its
      // properties that apply to numbers.
      NumberFormatInfo provider = new NumberFormatInfo();

      // These properties affect the conversion.
      provider.NegativeSign = "neg ";
      provider.PositiveSign = "pos ";

      // These properties do not affect the conversion.
      // The input string cannot have decimal and group separators.
      provider.NumberDecimalSeparator = ".";
      provider.NumberNegativePattern = 0;

      outputBlock.Text += String.Format("This example of\n" +
          "  Convert.ToSByte( string ) and \n" +
          "  Convert.ToSByte( string, IFormatProvider ) " +
          "\ngenerates the following output. It converts " +
          "several strings to \nSByte values, using " +
          "default formatting or a NumberFormatInfo object.\n") + "\n";
      outputBlock.Text += String.Format(format, "String to convert",
          "Default/exception", "Provider/exception") + "\n";
      outputBlock.Text += String.Format(format, "-----------------",
          "-----------------", "------------------") + "\n";

      // Convert strings, with and without an IFormatProvider.
      ConvertToSByte(outputBlock, "123", provider);
      ConvertToSByte(outputBlock, "+123", provider);
      ConvertToSByte(outputBlock, "pos 123", provider);
      ConvertToSByte(outputBlock, "-123", provider);
      ConvertToSByte(outputBlock, "neg 123", provider);
      ConvertToSByte(outputBlock, "123.", provider);
      ConvertToSByte(outputBlock, "(123)", provider);
      ConvertToSByte(outputBlock, "128", provider);
      ConvertToSByte(outputBlock, "-129", provider);
   }
}

/*
This example of
  Convert.ToSByte( string ) and
  Convert.ToSByte( string, IFormatProvider )
generates the following output. It converts several strings to
SByte values, using default formatting or a NumberFormatInfo object.

String to convert   Default/exception   Provider/exception
-----------------   -----------------   ------------------
123                 123                 123
+123                123                 FormatException
pos 123             FormatException     123
-123                -123                FormatException
neg 123             FormatException     -123
123.                FormatException     FormatException
(123)               FormatException     FormatException
128                 OverflowException   OverflowException
-129                OverflowException   FormatException
*/

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.