Javascript debugger
Website design
↑
ereg_replace
Replace regular expression
(PHP 4, PHP 5)
string ereg_replace ( string pattern, string replacement, string string )
Parameters
- pattern
A POSIX extended regular expression.
- replacement
If pattern contains parenthesized substrings, replacement may contain substrings of the form
\\, which will be replaced by the text matching the digit'th parenthesized substring;digit\\0will 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.- string
The input string.
Return Values
The modified string is returned. If no matches are found in string, then it will be returned unchanged.
Examples
For example, the following code snippet prints "This was a test" three times:
Example 1891. 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 1892. 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 1893. Replace URLs with links
<?php
$text = ereg_replace("[[:alpha:]]+://[^<>[:space:]]+[[:alnum:]/]",
"<a href=\"\\0\">\\0</a>", $text);
?>
Notes
preg_replace(), which uses a Perl-compatible regular expression syntax, is often a faster alternative to ereg_replace().