C# Int32 TryParse(String, NumberStyles, IFormatProvider, Int32)

Description

Int32 TryParse(String, NumberStyles, IFormatProvider, Int32)converts the string representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.

Syntax

Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) has the following syntax.


public static bool TryParse(
  string s,//w  ww.  ja va2  s  . c o m
  NumberStyles style,
  IFormatProvider provider,
  out int result
)

Parameters

Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) has the following parameters.

s - A string containing a number to convert. The string is interpreted using the style specified by style.
style - A bitwise combination of enumeration values that indicates the style elements that can be present in s. A typical value to specify is Integer.
provider - An object that supplies culture-specific formatting information about s.
result - When this method returns, contains the 32-bit signed integer value equivalent of the number contained in s, if the conversion succeeded, or zero if the conversion failed. The conversion fails if the s parameter is null or String.Empty, is not in a format compliant with style, or represents a number less than MinValue or greater than MaxValue. This parameter is passed uninitialized.

Returns

Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) method returns true if s was converted successfully; otherwise, false.

Example

The following example calls the Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) method with a number of different string and NumberStyles values.


using System;/*w  w  w.  j av  a 2s .  c  om*/
using System.Globalization;

public class StringParsing
{
   public static void Main()
   {
      string numericString;
      NumberStyles styles;

      numericString = "123456";
      styles = NumberStyles.Integer;
      CallTryParse(numericString, styles);

      numericString = "-12345";
      styles = NumberStyles.None;
      CallTryParse(numericString, styles);

      styles = NumberStyles.AllowLeadingSign;
      CallTryParse(numericString, styles);

      numericString = "123456-";
      CallTryParse(numericString, styles);

      styles = styles | NumberStyles.AllowTrailingSign;
      CallTryParse(numericString, styles);

      numericString = "$12345";
      styles = NumberStyles.Integer;
      CallTryParse(numericString, styles);

      styles = NumberStyles.Integer | NumberStyles.AllowCurrencySymbol;
      CallTryParse(numericString, styles);

      numericString = "12345.00";
      styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
      CallTryParse(numericString, styles);

      numericString = "12345.72";
      styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
      CallTryParse(numericString, styles);

      numericString = "12,345"; 
      styles = NumberStyles.Integer | NumberStyles.AllowThousands;
      CallTryParse(numericString, styles);

      numericString = "12E-01";
      styles = NumberStyles.Integer | NumberStyles.AllowExponent;
      CallTryParse(numericString, styles); 

      numericString = "12E03";
      CallTryParse(numericString, styles); 

      numericString = "80c1";
      CallTryParse(numericString, NumberStyles.HexNumber);

      numericString = "0x80C1";
      CallTryParse(numericString, NumberStyles.HexNumber);      
   }

   private static void CallTryParse(string stringToConvert, NumberStyles styles)
   {
      int number;
      CultureInfo provider;

      // If currency symbol is allowed, use en-US culture. 
      if ((styles & NumberStyles.AllowCurrencySymbol) > 0)
         provider = new CultureInfo("en-US");
      else
         provider = CultureInfo.InvariantCulture;

      bool result = Int32.TryParse(stringToConvert, styles, 
                                   provider, out number);
      if (result)
         Console.WriteLine("Converted '{0}' to {1}.", stringToConvert, number);
      else
         Console.WriteLine("Attempted conversion of '{0}' failed.", 
                           Convert.ToString(stringToConvert));
   }
}

The code above generates the following result.