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Regex.IsMatch Method (String)

Indicates whether the regular expression specified in the Regex constructor finds a match in the input string.

Namespace: System.Text.RegularExpressions
Assembly: System (in system.dll)

public bool IsMatch (
	string input
)
public boolean IsMatch (
	String input
)
public function IsMatch (
	input : String
) : boolean

Parameters

input

The string to search for a match.

Return Value

true if the regular expression finds a match; otherwise, false.

The following code example illustrates the use of this method to test whether a regular expression matches a given string.

using System;
using System.Text.RegularExpressions;

public class Test
{

    public static void Main ()
    {

    	  // Define a regular expression for currency values.
  	    Regex rx = new Regex(@"^-?\d+(\.\d{2})?$");
  	    
  	    // Define some test strings.
  	    string[] tests = {"-42", "19.99", "0.001", "100 USD"};
  	    
  	    // Check each test string against the regular expression.
  	    foreach (string test in tests)
  	    {
  	        if (rx.IsMatch(test))
  	        {
  	            Console.WriteLine("{0} is a currency value.", test);
  	        }
  	        else
  	        {
  	            Console.WriteLine("{0} is not a currency value.", test);
  	        }
  	    }
  	   
    }	
	
}

import System.*;
import System.Text.RegularExpressions.*;

public class Test
{
    public static void main(String[] args)
    {
        // Define a regular expression for currency values.
        Regex rx = new Regex("^-?\\d+(\\.\\d{2})?$");

        // Define some test strings.
        String tests[] =  { "-42", "19.99", "0.001", "100 USD" };

        // Check each test string against the regular expression.
        for (int iCtr = 0; iCtr < tests.get_Length(); iCtr++) {
            String test = (String)tests.get_Item(iCtr);
            if (rx.IsMatch(test)) {
                Console.WriteLine("{0} is a currency value.", test);
            }
            else {
                Console.WriteLine("{0} is not a currency value.", test);
            }
        }
    } //main 
} //Test

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0
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