Článek
11/18/2011

Int32.Parse Method (String)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Converts the string representation of a number to its 32-bit signed integer equivalent.

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

Syntax

'Declaration
Public Shared Function Parse ( _
    s As String _
) As Integer

public static int Parse(
    string s
)

Parameters

s
Type: System.String
A string containing a number to convert.

Return Value

Type: System.Int32
A 32-bit signed integer equivalent to the number contained in s.

Exceptions

Exception	Condition
ArgumentNullException	s is nulla null reference (Nothing in Visual Basic).
FormatException	s is not in the correct format.
OverflowException	s represents a number less than MinValue or greater than MaxValue.

Remarks

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 decimal digits, only leading and trailing spaces together with a leading sign are allowed. To explicitly define the style elements that can be present in s, use either the Int32.Parse(String, NumberStyles) or the Int32.Parse(String, NumberStyles, IFormatProvider) 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. To parse a string using the formatting information of some other culture, use the Byte.Parse(String, NumberStyles, IFormatProvider) method.

Examples

The following example demonstrates how to convert a string value into a 32-bit signed integer value using the Int32.Parse(String) method. It then displays the resulting integer value.

Module Example
   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Convert(outputBlock, "  179  ")
      Convert(outputBlock, " -204 ")
      Convert(outputBlock, " +809 ")
      Convert(outputBlock, "  178.3")
   End Sub

   Private Sub Convert(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal value As String)
      Try
         Dim number As Integer = Int32.Parse(value)
         outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) & vbCrLf
      Catch e As FormatException
         outputBlock.Text += String.Format("Unable to convert '{0}'.", value) & vbCrLf
      End Try
   End Sub
End Module
' This example displays the following output:
'       Converted '  179  ' to 179.
'       Converted ' -204 ' to -204.
'       Converted ' +809 ' to 809.
'       Unable to convert '  178.3'.

using System;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      Convert(outputBlock, "  179  ");
      Convert(outputBlock, " -204 ");
      Convert(outputBlock, " +809 ");
      Convert(outputBlock, "  178.3");
   }

   private static void Convert(System.Windows.Controls.TextBlock outputBlock, string value)
   {
      try
      {
         int number = Int32.Parse(value);
         outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) + "\n";
      }
      catch (FormatException)
      {
         outputBlock.Text += String.Format("Unable to convert '{0}'.", value) + "\n";
      }
   }
}
// This example displays the following output:
//       Converted '  179  ' to 179.
//       Converted ' -204 ' to -204.
//       Converted ' +809 ' to 809.
//       Unable to convert '  178.3'.

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.

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