PHP/String/String Matches

$: anchors a pattern to the end of a line or the end of the string

<?php
     $string = " is PHP";
     $pattern = "/PHP$/";
   
     if(preg_match($pattern, $string))
          print("Found a match!");
?>

A simple use of preg_match()

<?php
     $string = "PHP is the web scripting language";
     $pattern = "/PHP/";
   
     if(preg_match($pattern, $string))
          print("Found a match!");
?>

String match and if statement

<?php
     $string = "numbers 42";
     $pattern = "/[^0-9]$/";
   
     if(preg_match($pattern, $string))
          print("Found a match!");
?>

String match demo: |

<?php
     $string = "Cats coat dog date dig daughter catagory";
     $pattern = "/cat|dog/";
   
     if(preg_match($pattern, $string))
          print("Found a match!");
?>

String match demo: /[cd][oa][gt]/

<?php
     $string = "Cats coat dog date dig daughter catagory";
     $pattern = "/[cd][oa][gt]/";
   
     if(preg_match($pattern, $string))
          print("Found a match!");
?>

String matches: ^ (begine)

<?php
     $string = "PHP is ";
     $pattern = "/^PHP/";
   
     if(preg_match($pattern, $string))
          print("Found a match!");
?>

String matches: string start

<?php
     $pattern = "/^PHP$/";
   
     $string = "   PHP   ";
     if(preg_match($pattern, $string)){
          print("Found a match!");
     }
     
     $string = "PHP is ";
     if(preg_match($pattern, $string)){
          print("This line won"t print!");
     }     
?>

String match for domain name

<?
function simple_dot_com ($url) {
  return(ereg("^www\.[a-z]+\.ru$", $url));
}
$urls_to_test = 
   array("www.ibm.ru", "www.java.sun.ru", 
         "www.zend.ru", "java.sun.ru", 
         "www.java.sun.ru", "www.php.net", 
         "www.IBM.ru",
         "www.Web addresses can\"t have spaces.ru");
while($test = array_pop($urls_to_test)){
  if (simple_dot_com($test))
    print("\"$test\" is a simple dot-com<BR>");
  else 
    print("\"$test\" is NOT a simple dot-com<BR>");
   
}
?>