Create URL with only A-Z characters that includes variable and extension - php

Question

I am trying to create file links based a variable which has a "prefix" and an extension at the end.
Here's what I have:
$url = "http://www.example.com/mods/" . ereg("^[A-Za-z_\-]+$", $title) . ".php";
Example output of what I wish to have outputted (assuming $title = testing;):
http://www.example.com/mods/testing.php
What it currently outputs:
http://www.example.com/mods/.php
Thanks in advance!

Answer 1

Perhaps this is what you need:
$title = "testing";
if(preg_match("/^[A-Za-z_\-]+$/", $title, $match)){
$url = "http://www.example.com/mods/".$match[0].".php";
}
else{
// Think of something to do here...
}
Now $url is http://www.example.com/mods/testing.php.

Answer 2

Do you want to keep letters and remove all other chars in the URL?
In this case the following should work:
$title = ...
$fixedtitle=preg_replace("/[^A-Za-z_-]/", "", $title);
$url = "http://www.example.com/mods/".$fixedtitle.".php";
the inverted character class will remove everything you do not want.

Answer 3

OK first it's important for you to realize that ereg() is deprecated and will eventually not be available as a command for php, so to prevent an error down the road you should use preg_match instead.
Secondly, both ereg() and preg_match output the status of the match, not the match itself. So
ereg("^[A-Za-z_\-]+$", $title)
will output an integer equal to the length of the string in $title, 0 if there's no match and 1 if there's a match but you didn't pass it another variable to store the matches in.
I'm not sure why it's displaying
http://www.example.com/mods/.php
It should actually be outputting
http://www.example.com/mods/1.php
if everything was working correctly. So there is something going on there, and it's definitely not doing what you want it to. You need to pass another variable to the function that will store all the matches found. If the match is successful (which you can check using the return value of the function) then that variable will be an array of all matches.
Note that with preg_match by default only the first match will be returned. but it will still generate an array (which can be used to get isolated portions of the match) whereas preg_match_all will match multiple things.
See http://www.php.net/manual/en/function.preg-match.php for more details.
Your regex looks more or less correct
So the proper code should look something like:
$title = 'testing'; //making sure that $title is what we think it is
if (preg_match('/^[A-Za-z_\-]+$/',$title,$matches)) {
$url = "http://www.example.com/mods/" . $matches[0] . ".php";
} else {
//match failed, put error code in here
}