.NET Framework Class Library
Int32TryParse 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)
Syntax
Public Shared Function TryParse ( _
	s As [%$TOPIC/f02979c7_en-us_VS_110_1_0_0_0_0%], _
	<[%$TOPIC/f02979c7_en-us_VS_110_1_0_0_0_1%]> ByRef result As [%$TOPIC/f02979c7_en-us_VS_110_1_0_0_0_2%] _
) As [%$TOPIC/f02979c7_en-us_VS_110_1_0_0_0_3%]
public static [%$TOPIC/f02979c7_en-us_VS_110_1_0_1_0_0%] TryParse(
	[%$TOPIC/f02979c7_en-us_VS_110_1_0_1_0_1%] s,
	out [%$TOPIC/f02979c7_en-us_VS_110_1_0_1_0_2%] result
)
public:
static [%$TOPIC/f02979c7_en-us_VS_110_1_0_2_0_0%] TryParse(
	[%$TOPIC/f02979c7_en-us_VS_110_1_0_2_0_1%]^ s, 
	[[%$TOPIC/f02979c7_en-us_VS_110_1_0_2_0_2%]] [%$TOPIC/f02979c7_en-us_VS_110_1_0_2_0_3%]% result
)
static member TryParse : 
        s:[%$TOPIC/f02979c7_en-us_VS_110_1_0_3_0_0%] * 
        result:[%$TOPIC/f02979c7_en-us_VS_110_1_0_3_0_1%] byref -> [%$TOPIC/f02979c7_en-us_VS_110_1_0_3_0_2%]
public static function TryParse(
	s : [%$TOPIC/f02979c7_en-us_VS_110_1_0_4_0_0%], 
	result : [%$TOPIC/f02979c7_en-us_VS_110_1_0_4_0_1%]
) : [%$TOPIC/f02979c7_en-us_VS_110_1_0_4_0_2%]

Parameters

s
Type: SystemString

A string containing a number to convert.

result
Type: SystemInt32

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 or StringEmpty, 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: SystemBoolean
true if s was converted successfully; otherwise, false.
Remarks

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 NumberStylesInteger 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 Int32TryParse(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 Int32TryParse(String, NumberStyles, IFormatProvider, Int32) overload.

Examples

The following example calls the Int32TryParse(String, Int32) method with a number of different string values.

Module Example
   Public Sub Main()
      Dim values() As String = { Nothing, "160519", "9432.0", "16,667",
                                 "   -322   ", "+4302", "(100);", 
                                 "01FA" }

      For Each value In values
         Dim number As Integer 

         Dim result As Boolean = Int32.TryParse(value, number)
         If result Then
            Console.WriteLine("Converted '{0}' to {1}.", value, number)
         Else
            Console.WriteLine("Attempted conversion of '{0}' failed.", 
                              If(value Is Nothing, "<null>", value))
         End If      
      Next 
   End Sub 
End Module 
' The example displays the following output to the console: 
'       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.
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.
using namespace System;


   void TryToParse(String^ value)
   {
      Int32 number;
      bool result = Int32::TryParse(value, number);
      if (result) {
         Console::WriteLine("Converted '{0}' to {1}.", value, number);
      }
      else {
         if (value == nullptr) value = "";
         Console::WriteLine("Attempted conversion of '{0}' failed.", value);
      }
   }


void main()
{
      TryToParse(nullptr);
      TryToParse("160519");
      TryToParse("9432.0");
      TryToParse("16,667");
      TryToParse("   -322   ");
      TryToParse("+4302");
      TryToParse("(100);");
      TryToParse("01FA");
}
// The example displays the following output: 
//      Attempted conversion of '' 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.
Version Information

.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

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8