ToUInt16 Method (String)

Convert.ToUInt16 Method (String)

[ 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 16-bit unsigned integer.

This API is not CLS-compliant. 

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

'Declaration
<CLSCompliantAttribute(False)> _
Public Shared Function ToUInt16 ( _
	value As String _
) As UShort

Parameters

value
Type: System.String
A String containing a number to convert.

Return Value

Type: System.UInt16
A 16-bit unsigned integer equivalent to the value of value.
-or-
Zero if value is Nothing.

ExceptionCondition
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.

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

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 code example converts String representations of 16-bit unsigned integers with the ToUInt16 method, using default formatting.


' Example of the Convert.ToUInt16( String ) and 
' Convert.ToUInt16( 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 ConvertToUInt16(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 UInt16 without a format provider.
      Try
         defaultValue = Convert.ToUInt16(numericStr)
      Catch ex As Exception
         defaultValue = GetExceptionType(ex)
      End Try

      ' Convert numericStr to UInt16 with a format provider.
      Try
         providerValue = Convert.ToUInt16(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.PositiveSign = "pos "
      provider.NegativeSign = "neg "

      ' These properties do not affect the conversion.
      ' The input string cannot have decimal and group separators.
      provider.NumberDecimalSeparator = "."
      provider.NumberGroupSeparator = ","
      provider.NumberGroupSizes = New Integer() {3}

      outputBlock.Text &= String.Format("This example of" & vbCrLf & _
          "  Convert.ToUInt16( String ) and " & vbCrLf & _
          "  Convert.ToUInt16( String, IFormatProvider ) " & _
          vbCrLf & "generates the following output. It " & _
          "converts several strings to unsigned " & vbCrLf & _
          "Short 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.
      ConvertToUInt16(outputBlock, "34567", provider)
      ConvertToUInt16(outputBlock, "+34567", provider)
      ConvertToUInt16(outputBlock, "pos 34567", provider)
      ConvertToUInt16(outputBlock, "34567.", provider)
      ConvertToUInt16(outputBlock, "34,567", provider)
      ConvertToUInt16(outputBlock, "65535", provider)
      ConvertToUInt16(outputBlock, "65536", provider)
      ConvertToUInt16(outputBlock, "-1", provider)
   End Sub
End Module

' This example of
'   Convert.ToUInt16( String ) and
'   Convert.ToUInt16( String, IFormatProvider )
' generates the following output. It converts several strings to unsigned
' Short values, using default formatting or a NumberFormatInfo object.
' 
' String to convert   Default/exception   Provider/exception
' -----------------   -----------------   ------------------
' 34567               34567               34567
' +34567              34567               FormatException
' pos 34567           FormatException     34567
' 34567.              FormatException     FormatException
' 34,567              FormatException     FormatException
' 65535               65535               65535
' 65536               OverflowException   OverflowException
' -1                  OverflowException   FormatException


Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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