ereg_replace
eregi_replace
POSIX Regex Functions
PHP Manual

# ereg

(PHP 4, PHP 5)

ereg — 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 and REMOVED as of PHP 6.0.0. 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, calling this function will issue an `E_DEPRECATED` notice.

> Note: preg_match(), which uses a Perl-compatible regular expression syntax, is often a faster alternative to ereg().

### See Also

- eregi() - Case insensitive regular expression match
- ereg_replace() - Replace regular expression
- eregi_replace() - Replace regular expression case insensitive
- preg_match() - Perform a regular expression match
- strpos() - Find position of first occurrence of a string
- strstr() - Find first occurrence of a string
- quotemeta() - Quote meta characters

ereg_replace
eregi_replace
POSIX Regex Functions
PHP Manual