Php Tutorials

Php ereg_replace() Function

The ereg_replace() function searches for string specified by pattern and replaces pattern with replacement if found. The ereg_replace() function operates under the same premises as ereg(), except that the functionality is extended to finding and replacing pattern instead of simply locating it.

Syntax

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

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.

Example 1

Simple String Replacement, Replacing “five” with “ten” in “I have five mangoes” String:

echo ereg_replace("five", "ten", "I have five mangoes");

Output

From: I have five mangoes
To: I have ten mangoes

Example 2

Simple String Replacement, Replacing “to Buy Mangoes” with “Bananas” in “I like Bananas!” String:

$string = "I like Bananas";
echo ereg_replace("Bananas", "to Buy Mangoes", $string);

Output

From: I like Bananas!
To: I like to Buy Mangoes!

Example 3

Simple String Replacement, Replacing “Windows” with “Mac Ox” in “I like Mac Ox!” String:

$string = "I like Mac Ox!";
$pattern = "Mac Ox";
$replacement = "Windows";
echo ereg_replace($pattern, $replacement, $string);

Output

From: I like Mac Ox!
To: I like Windows!

Example 4

Simple String Replacement, Replacing Spaces between words with Dashes(-) String:

$string = "Learn how to build your own website";
$pattern = " ";
$replacement = "-";
echo ereg_replace($pattern, $replacement, $string);

Output

From: Learn how to build your own website.
To: Learn-how-to-buld-your-own-website.

Example 5

Simple String Replacement, Removing a word from the string:

$string = "How to make money online";
$pattern = " online";
$replacement = "";
echo ereg_replace($pattern, $replacement, $string);

Output

From: How to make money online
To: How to make money

Example 6

Simple String Replacement, highlighting a simple word:

$string = "Learn Php step by step here";
$pattern = "Php";
$replacement = "<font color=red>Php</font>";
echo ereg_replace($pattern, $replacement, $string);

Output

From: Learn Php step by step here
To: Learn Php step by step here

Example 7

Simple String Replacement, highlights the recognized patterns (a good tool for experiments) :

$string = "Learn Php step by step here";
$pattern = "Php";
$replacement = "<font color=red>\\0</font>";
echo ereg_replace($pattern, $replacement, $string);

Output

From: Learn Php step by step here
To: Learn Php step by step here

Example 8

Simple String Replacement, Make all url starts with “http://” clickable:

$string = "Do you want to learn php, please go to http://www.urphp.com";
echo ereg_replace("[a-zA-Z]+://([.]?[a-zA-Z0-9_/-])*", "<a href=\"\\0\">\\0</a>", $string);

Output

From: Do you want to learn php, please go to www.urphp.com
To: Do you want to learn php, please go to www.urphp.com

Example 9

Simple String Replacement, Make all url starts with “www” clickable:

$string = "Do you want to learn php, please go to www.urphp.com";
echo ereg_replace("(^| )(www([.]?[a-zA-Z0-9_/-])*)", "\\1<a href=\"http://\\2\">\\2</a>", $string);

Output

From: Do you want to learn php, please go to www.urphp.com
To: Do you want to learn php, please go to www.urphp.com