PHP Manual: Regular expression match

Description

int ereg ( string $pattern , string $string [, array &$regs ] )

Searches a string for matches to the regular expression given in pattern in a case-sensitive way.

Warning

This function has been DEPRECATED as of PHP 5.3.0. Relying on this feature is highly discouraged.

Parameters

pattern

Case sensitive regular expression.

string

The input string.

regs

If matches are found for parenthesized substrings of pattern and the function is called with the third argument regs, the matches will be stored in the elements of the array regs.

$regs[1] will contain the substring which starts at the first left parenthesis; $regs[2] will contain the substring starting at the second, and so on. $regs[0] will contain a copy of the complete string matched.

Return Values

Returns the length of the matched string if a match for pattern was found in string, or FALSE if no matches were found or an error occurred.

If the optional parameter regs was not passed or the length of the matched string is 0, this function returns 1.

Changelog

Version	Description
4.1.0	Up to (and including) PHP 4.1.0 `$regs` will be filled with exactly ten elements, even though more or fewer than ten parenthesized substrings may actually have matched. This has no effect on ereg's ability to match more substrings. If no matches are found, $regs will not be altered by ereg.

Examples

Example #1 ereg example

The following code snippet takes a date in ISO format (YYYY-MM-DD) and prints it in DD.MM.YYYY format:


<?php
if (ereg ("([0-9]{4})-([0-9]{1,2})-([0-9]{1,2})", $date, $regs)) {
    echo "$regs[3].$regs[2].$regs[1]";
} else {
    echo "Invalid date format: $date";
}
?>

Notes

Note:
As of PHP 5.3.0, the regex extension is deprecated in favor of the PCRE extension. Calling this function will issue an E_DEPRECATED notice. See the list of differences for help on converting to PCRE.

Tip

ereg is deprecated as of PHP 5.3.0. preg_match is the suggested alternative to this function.