Convert.ToInt16 Method (String, IFormatProvider)

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

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

Syntax

'Declaration
Public Shared Function ToInt16 ( _
    value As String, _
    provider As IFormatProvider _
) As Short
public static short ToInt16(
    string value,
    IFormatProvider provider
)

Parameters

Return Value

Type: System.Int16
A 16-bit signed integer equivalent to the value of value.
-or-
Zero if value is nulla null reference (Nothing in Visual Basic).

Exceptions

Exception Condition
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 Int16.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 16-bit integers with the ToInt16 method, using an IFormatProvider object.

' Example of the Convert.ToInt16( String ) and 
' Convert.ToInt16( 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 ConvertToInt16(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 Int16 without a format provider.
      Try
         defaultValue = Convert.ToInt16(numericStr)
      Catch ex As Exception
         defaultValue = GetExceptionType(ex)
      End Try

      ' Convert numericStr to Int16 with a format provider.
      Try
         providerValue = Convert.ToInt16(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.NumberGroupSeparator = ","
      provider.NumberGroupSizes = New Integer() {3}
      provider.NumberNegativePattern = 0

      outputBlock.Text &= String.Format("This example of" & vbCrLf & _
          "  Convert.ToInt16( String ) and " & vbCrLf & _
          "  Convert.ToInt16( String, IFormatProvider ) " & _
          vbCrLf & "generates the following output. It " & _
          "converts several strings to " & 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.
      ConvertToInt16(outputBlock, "12345", provider)
      ConvertToInt16(outputBlock, "+12345", provider)
      ConvertToInt16(outputBlock, "pos 12345", provider)
      ConvertToInt16(outputBlock, "-12345", provider)
      ConvertToInt16(outputBlock, "neg 12345", provider)
      ConvertToInt16(outputBlock, "12345.", provider)
      ConvertToInt16(outputBlock, "12,345", provider)
      ConvertToInt16(outputBlock, "(12345)", provider)
      ConvertToInt16(outputBlock, "32768", provider)
      ConvertToInt16(outputBlock, "-32769", provider)
   End Sub
End Module

' This example of
'   Convert.ToInt16( String ) and
'   Convert.ToInt16( String, IFormatProvider )
' generates the following output. It converts several strings to
' Short values, using default formatting or a NumberFormatInfo object.
' 
' String to convert   Default/exception   Provider/exception
' -----------------   -----------------   ------------------
' 12345               12345               12345
' +12345              12345               FormatException
' pos 12345           FormatException     12345
' -12345              -12345              FormatException
' neg 12345           FormatException     -12345
' 12345.              FormatException     FormatException
' 12,345              FormatException     FormatException
' (12345)             FormatException     FormatException
' 32768               OverflowException   OverflowException
' -32769              OverflowException   FormatException
// Example of the Convert.ToInt16( string ) and 
// Convert.ToInt16( 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 ConvertToInt16(System.Windows.Controls.TextBlock outputBlock, string numericStr,
       IFormatProvider provider)
   {
      object defaultValue;
      object providerValue;

      // Convert numericStr to Int16 without a format provider.
      try
      {
         defaultValue = Convert.ToInt16(numericStr);
      }
      catch (Exception ex)
      {
         defaultValue = GetExceptionType(ex);
      }

      // Convert numericStr to Int16 with a format provider.
      try
      {
         providerValue = Convert.ToInt16(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.NumberGroupSeparator = ",";
      provider.NumberGroupSizes = new int[] { 3 };
      provider.NumberNegativePattern = 0;

      outputBlock.Text += String.Format("This example of\n" +
          "  Convert.ToInt16( string ) and \n" +
          "  Convert.ToInt16( string, IFormatProvider ) " +
          "\ngenerates the following output. It converts " +
          "several strings to \nshort 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.
      ConvertToInt16(outputBlock, "12345", provider);
      ConvertToInt16(outputBlock, "+12345", provider);
      ConvertToInt16(outputBlock, "pos 12345", provider);
      ConvertToInt16(outputBlock, "-12345", provider);
      ConvertToInt16(outputBlock, "neg 12345", provider);
      ConvertToInt16(outputBlock, "12345.", provider);
      ConvertToInt16(outputBlock, "12,345", provider);
      ConvertToInt16(outputBlock, "(12345)", provider);
      ConvertToInt16(outputBlock, "32768", provider);
      ConvertToInt16(outputBlock, "-32769", provider);
   }
}

/*
This example of
  Convert.ToInt16( string ) and
  Convert.ToInt16( string, IFormatProvider )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.

String to convert   Default/exception   Provider/exception
-----------------   -----------------   ------------------
12345               12345               12345
+12345              12345               FormatException
pos 12345           FormatException     12345
-12345              -12345              FormatException
neg 12345           FormatException     -12345
12345.              FormatException     FormatException
12,345              FormatException     FormatException
(12345)             FormatException     FormatException
32768               OverflowException   OverflowException
-32769              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.