Preg_replace

Spudgun

Hi
Could someone point me in the direction of a pre_replace tutorial. I've read the manual, checked some sites and looked at the examples here in this forum, but some of the syntax is confusing.
All help appreciated.
Thanks

leetcrew

do you mean preg_replace() ?


$string = "a quick brown fox...";

// print $string
printf ("%s <br>", $string );
// the output is: a quick brown fox...



// using preg_replace

$new_string = peg_replace ("brown", "black", $string );

// print $new_string
printf ("%s <br>", $new_string );

// the output is: a quick black fox...

here's the syntax


preg_replace ( pattern as string, replacement as string, source as string);

for more info, download the php manual...

another example

<?php
$str = "April 15, 2003";
$pattern = "/(\w+) (\d+), (\d+)/i";
$replacement = "\${1}1,\$3";
print preg_replace($pattern, $replacement, $string);

/* Output
   ======

April1,2003

 */
?>

leetcrew

example 2:

<?php
$string = "The quick brown fox jumped over the lazy dog.";

$patterns[0] = "/quick/";
$patterns[1] = "/brown/";
$patterns[2] = "/fox/";

$replacements[2] = "bear";
$replacements[1] = "black";
$replacements[0] = "slow";

print preg_replace($patterns, $replacements, $string);

/* Output
   ======

The bear black slow jumped over the lazy dog.

*/

/* By ksorting patterns and replacements,
   we should get what we wanted. */

ksort($patterns);
ksort($replacements);

print preg_replace($patterns, $replacements, $string);

/* Output
   ======

The slow black bear jumped over the lazy dog.

*/

?>

Spudgun

Thanks leetcrew. I did mean preg_replace().

Which would be best to use in the following case - ereg_replace or preg_replace..

I have a form that is submitted containing html. Within the HTML are hyperlinks. I need to search through the html for the hyperlinks, and change them in the following way:

Original hyperlink: <a href="http://www.mywebserver.com/testpage.htm" target="_blank">Click</a>

New Hyperlink:
<a href="http://www.webserver.com/linkpage.php?e=$usn&id=$subj&red=$hyperlink (where $hyperlink is the original hyperlink)

On top of that, I obviously need to keep the target reference on the new URL.

I've tried using eregi_replace for this - my "code" (if you can call it that) is below...

$pattern = "(<a href=\"http://\")+[[:alnum:]][^>]$";
$translation = "<a href=\"http://www.webserver.com/linkpage.php?e=$usn&id=subj&red=$pattern\"";
 $bodytext = eregi_replace($pattern,$translation,$bodytext);

Please bear in mind, this is the first time I've ever looked at preg_replace and ereg_replace...

If anyone could point out my mistakes here I'd be really grateful.
Thanks

leetcrew

try this code... i can't test it here coz i dont have a php here


$hyperlink = "<a href='http://www.mywebserver.com/testpage.htm' target='_blank'>Click</a>";
// remove <a href='
$hyperlink = preg_replace ( "<a href='", "", $hyperlink );
// remove ' target='_blank'>Click</a>";
$hyperlink = preg_replace ( "' target='_blank'>Click</a>", "", $hyperlink );

i dont use ereg_replace()

Spudgun

Thanks Leetcrew - I can see what you're doing here but I'm getting errors with your script.

I'm not sure if this is going to solve my problem though.

I have a variable $html_body as below:

$html_body ="<HTML><HEAD><TITLE>Text</TITLE>
</HEAD><BODY>
Here is some text and within it are <img src=\"http://www.myserver.com/image.gif> and also
some <a href=\"http://www.webserver.com/pageindex/pagelink.htm\" target=\"_blank\">hyperlinks</A> and all sorts of stuff. ";

I do not know what the hyperlinks will be when the text is submitted - but I need to parse $html_body and pick up the hyperlinks and change them to be:

<a href=\"www.differentserver.com/myspecificpage.php?e=http://www.webserver.com/pageindex/pagelink.htm\" target=\"_blank\">hyperlinks</A>

Does that make more sense? I'm really struggling with this now.
Please help.

badboy

I want to remove special & potentialy dangerous characters from my web form submissions.
eg: . $ /

I've come up with the following but it won't replace the /
I know it must be simple but it's now getting on my nerves ?*>^

$address= 241 .Park$ Av/enue

print ereg_replace("[.\$]+([/])", "", $address)

Prints: 241 Park Av/enue

Thanks,
Badboy

laserlight

why not use:

$address = "241 .Park$ Av/enue";
$address = preg_replace("/[.\$\/]/", "", $address);
echo $address;

in this case I think the + is not needed, since consecutive instances of the characters replaced by a "" would be the same as each replaced by a ""