   #PHP Manual Regular Expression Functions (POSIX Extended) Regular
   Expression Functions (POSIX Extended) ereg

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                                 ereg_replace

   (PHP 3, PHP 4 )
   ereg_replace -- Replace regular expression

Description

   string ereg_replace ( string pattern, string replacement, string
   string)

   This function scans string for matches to pattern, then replaces the
   matched text with replacement.

   The modified string is returned. (Which may mean that the original
   string is returned if there are no matches to be replaced.)

   If pattern contains parenthesized substrings, replacement may contain
   substrings of the form \\digit, which will be replaced by the text
   matching the digit'th parenthesized substring; \\0 will produce the
   entire contents of string. Up to nine substrings may be used.
   Parentheses may be nested, in which case they are counted by the
   opening parenthesis.

   If no matches are found in string, then string will be returned
   unchanged.

   For example, the following code snippet prints "This was a test" three
   times:

   Example 1. ereg_replace() example
   <?php
   $string = "This is a test";
   echo str_replace(" is", " was", $string);
   echo ereg_replace("( )is", "\\1was", $string);
   echo ereg_replace("(( )is)", "\\2was", $string);
   ?>

   One thing to take note of is that if you use an integer value as the
   replacement parameter, you may not get the results you expect. This is
   because ereg_replace() will interpret the number as the ordinal value
   of a character, and apply that. For instance:

   Example 2. ereg_replace() example
   <?php
   /* This will not work as expected. */
   $num = 4;
   $string = "This string has four words.";
   $string = ereg_replace('four', $num, $string);
   echo $string;   /* Output: 'This string has   words.' */
   /* This will work. */
   $num = '4';
   $string = "This string has four words.";
   $string = ereg_replace('four', $num, $string);
   echo $string;   /* Output: 'This string has 4 words.' */
   ?>

   Example 3. Replace URLs with links
   <?php
   $text = ereg_replace("[[:alpha:]]+://[^<>[:space:]]+[[:alnum:]/]",
                        "<a href=\"\\0\">\\0</a>", $text);
   ?>

     Tip: preg_replace(), which uses a Perl-compatible regular
     expression syntax, is often a faster alternative to ereg_replace().

   See also ereg(), eregi(), eregi_replace(), str_replace(), and
   preg_match().
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