This documentation is archived and is not being maintained.

Convert.ToUInt16 Method (String, IFormatProvider)

Updated: May 2009

Converts the specified string representation of a number to an equivalent 16-bit unsigned integer, using the specified culture-specific formatting information.

This API is not CLS-compliant. 

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

public static ushort ToUInt16(
	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.UInt16
A 16-bit unsigned integer that is equivalent to the number in value, or 0 (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 UInt16.MinValue or greater than UInt16.MaxValue.

The return value is the result of invoking UInt16.Parse on value.

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 UInt16.TryParse method instead. It returns a Boolean value that indicates whether the conversion succeeded or failed.

The following example defines a custom NumberFormatInfo object that recognizes the string "pos" as the positive sign and the string "neg" as the negative sign. It then attempts to convert each element of a numeric string array to an integer using both this provider and the NumberFormatInfo provider for the invariant culture.

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 numbers.
      NumberFormatInfo provider = new NumberFormatInfo();
      provider.PositiveSign = "pos ";
      provider.NegativeSign = "neg ";

      // Define an array of strings to convert to UInt16 values.
      string[] values= { "34567", "+34567", "pos 34567", "34567.", 
                         "34567.", "65535", "65535", "65535" };         

      foreach (string value in values)
         Console.Write("{0,-12:}  -->  ", value);
         try {
            Console.WriteLine("{0,17}", Convert.ToUInt16(value, provider));
         catch (FormatException e) {       
            Console.WriteLine("{0,17}", e.GetType().Name);
// The example displays the following output: 
//       34567         -->              34567 
//       +34567        -->    FormatException 
//       pos 34567     -->              34567 
//       34567.        -->    FormatException 
//       34567.        -->    FormatException 
//       65535         -->              65535 
//       65535         -->              65535 
//       65535         -->              65535

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.