ToByte Method (String, IFormatProvider)

Convert.ToByte Method (String, IFormatProvider)

Updated: May 2009

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 that contains the number to convert.

Type: System.IFormatProvider

An object that supplies culture-specific formatting information.

Return Value

Type: System.Byte
An 8-bit unsigned integer that is equivalent to value, or zero if value is null.


value does not consist of an optional sign followed by a sequence of digits (0 through 9).


value represents a number that is less than Byte.MinValue or greater than Byte.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 object 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 example creates a custom NumberFormatInfo object that defines the positive sign as "pos" and the negative sign as "neg", which it uses in calls to the ToByte(String, IFormatProvider) method. It then calls the ToByte(String, IFormatProvider) method repeatedly to convert each element in a string array to a Byte value.

using System;
using System.Globalization;

public class Example
   public static void Main()
      // Create a NumberFormatInfo object and set several of its 
      // properties that apply to unsigned bytes.
      NumberFormatInfo provider = new NumberFormatInfo();

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

      // This property does not affect the conversion. 
      // The input string cannot have a decimal separator.
      provider.NumberDecimalSeparator = ".";

      // Define an array of numeric strings.
      string[] numericStrings = { "234", "+234", "pos 234", "234.", "255", 
                                  "256", "-1" };

      foreach (string numericString in numericStrings)
         Console.Write("'{0,-8}' ->   ", numericString);
         try {
            byte number = Convert.ToByte(numericString, provider);
         catch (FormatException) {
            Console.WriteLine("Incorrect Format");
         catch (OverflowException) {
            Console.WriteLine("Overflows a Byte");
// The example displays the following output: 
//       '234     ' ->   234 
//       '+234    ' ->   Incorrect Format 
//       'pos 234 ' ->   234 
//       '234.    ' ->   Incorrect Format 
//       '255     ' ->   255 
//       '256     ' ->   Overflows a Byte 
//       '-1      ' ->   Incorrect Format

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

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

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0




May 2009

Expanded the Remarks section.

Customer feedback.

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