ToByte Method (String, IFormatProvider)

Convert.ToByte Method (String, IFormatProvider)

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

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

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

public static byte ToByte(
	string value,
	IFormatProvider provider


Type: System.String
A String containing a number to convert.
Type: System.IFormatProvider
An IFormatProvider interface implementation that supplies culture-specific formatting information.

Return Value

Type: System.Byte
An 8-bit signed integer equivalent to the value of value.
Zero if value is null.


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


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

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 null, the NumberFormatInfo for the current culture is used.

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

The following code example converts String representations of unsigned Byte values with the ToByte method, using an IFormatProvider object.

// Example of the Convert.ToByte( string ) and 
// Convert.ToByte( 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 ConvertToByte(System.Windows.Controls.TextBlock outputBlock, string numericStr,
       IFormatProvider provider)
      object defaultValue;
      object providerValue;

      // Convert numericStr to Byte without a format provider.
         defaultValue = Convert.ToByte(numericStr);
      catch (Exception ex)
         defaultValue = GetExceptionType(ex);

      // Convert numericStr to Byte with a format provider.
         providerValue = Convert.ToByte(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 = ".";

      outputBlock.Text += String.Format("This example of\n" +
          "  Convert.ToByte( string ) and \n" +
          "  Convert.ToByte( string, IFormatProvider ) " +
          "\ngenerates the following output. It converts " +
          "several strings to \nbyte 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.
      ConvertToByte(outputBlock, "234", provider);
      ConvertToByte(outputBlock, "+234", provider);
      ConvertToByte(outputBlock, "pos 234", provider);
      ConvertToByte(outputBlock, "234.", provider);
      ConvertToByte(outputBlock, "255", provider);
      ConvertToByte(outputBlock, "256", provider);
      ConvertToByte(outputBlock, "-1", provider);

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

String to convert   Default/exception   Provider/exception
-----------------   -----------------   ------------------
234                 234                 234
+234                234                 FormatException
pos 234             FormatException     234
234.                FormatException     FormatException
255                 255                 255
256                 OverflowException   OverflowException
-1                  OverflowException   FormatException

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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