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ereg_replace

(PHP 4, PHP 5)

ereg_replace — Replace regular expression

설명

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

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

매개변수

pattern

A POSIX extended regular expression.

replacement

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.

string

The input string.

반환값

The modified string is returned. If no matches are found in string , then it will be returned unchanged.

예제

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);
?>

주의

Tip

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