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Int32.TryParse Method (String, Int32)

Converts the string representation of a number to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.

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

public static bool TryParse(
	string s,
	out int result
)

Parameters

s
Type: System.String

A string containing a number to convert.

result
Type: System.Int32

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 of the correct format, or represents a number less than MinValue or greater than MaxValue. This parameter is passed uninitialized; any value originally supplied in result will be overwritten.

Return Value

Type: System.Boolean
true if s was converted successfully; otherwise, false.

The TryParse method is like the Parse method, except the TryParse method does not throw an exception if the conversion fails. It eliminates the need to use exception handling to test for a FormatException in the event that s is invalid and cannot be successfully parsed.

The s parameter contains a number of the form:

[ws][sign]digits[ws]

Items in square brackets ([ and ]) are optional. The following table describes each element.

Element

Description

ws

Optional white space.

sign

An optional sign.

digits

A sequence of digits ranging from 0 to 9.

The s parameter is interpreted using the NumberStyles.Integer style. In addition to the decimal digits, only leading and trailing spaces together with a leading sign are allowed. To explicitly define the style elements together with the culture-specific formatting information that can be present in s, use the Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) method.

The s parameter is parsed using the formatting information in a NumberFormatInfo object initialized for the current system culture. For more information, see CurrentInfo.

This overload of the TryParse method interprets all digits in the s parameter as decimal digits. To parse the string representation of a hexadecimal number, call the Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) overload.

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

using System;

public class Example
{
   public static void Main()
   {
      String[] values = { null, "160519", "9432.0", "16,667",
                          "   -322   ", "+4302", "(100);", "01FA" };
      foreach (var value in values) {
         int number;

         bool result = Int32.TryParse(value, out number);
         if (result)
         {
            Console.WriteLine("Converted '{0}' to {1}.", value, number);         
         }
         else
         {
//            if (value == null) value = ""; 
            Console.WriteLine("Attempted conversion of '{0}' failed.", 
                               value == null ? "<null>" : value);
         }
      }
   }
}
// The example displays the following output: 
//       Attempted conversion of '<null>' failed. 
//       Converted '160519' to 160519. 
//       Attempted conversion of '9432.0' failed. 
//       Attempted conversion of '16,667' failed. 
//       Converted '   -322   ' to -322. 
//       Converted '+4302' to 4302. 
//       Attempted conversion of '(100);' failed. 
//       Attempted conversion of '01FA' failed.

Some of the strings that the TryParse(String, Int32) method is unable to convert in this example are:

  • "9432.0". The conversion fails because the string cannot contain a decimal separator; it must contain integral digits only.

  • "16,667". The conversion fails because the string cannot contain group separators; it must contain integral digits only.

  • "(100)". The conversion fails because the string cannot contain a negative sign other than the one defined by the current culture's NumberFormatInfo.NegativeSign and NumberFormatInfo.NumberNegativePattern properties.

  • "01FA". The conversion fails because the string cannot contain hexadecimal digits; it must contain decimal digits only.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
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