Problem with strtotime in PHP

Today I found an interesting issue. Please try this following PHP code:
print strtotime("18/03/2012 06:08 am");
I didn't see any output. Then I looked at the documentation and found the following line:

Dates in the m/d/y or d-m-y formats are disambiguated by looking at the separator between the various components: if the separator is a slash (/), then the American m/d/y is assumed; whereas if the separator is a dash (-) or a dot (.), then the European d-m-y format is assumed.

So I had to replace "/" with "-" using str_replace and that worked!
print strtotime("18-03-2012 06:08 am");
Output:
1332029280

Phone Number Extractor in PHP

Here is a function to parse the content of a web page and extract phone / fax numbers (USA only). Regular expression is used to parse phone numbers.

 function extract_phone_numbers ($html_content)    
 {    
     $html_content = preg_replace("/[\s\+\-\(\)\.]/", "", $html_content);    
     $ara = array();    
     if (preg_match_all('/\D(\d{10})\D/', $html_content, $data)) {        
         $ara = array_unique($data[1]);        
     }    
     if (preg_match_all('/1(\d{10})\D/', $html_content, $data)) {        
         $ara = array_unique(array_merge($ara, $data[1]));    
     }    
     if (preg_match_all('/^(\d{10})$/', $html_content, $data)) {        
         $ara = array_unique(array_merge($ara, $data[1]));    
     }    
     return $ara;    
 }    

Email extractor in PHP using regex

Today, I am sharing my PHP code that extracts email address from html source of an URL. It uses regular expression to parse email address.

 function extract_email_addresses ($html_source)    
 {    
     $html_source = str_replace("(at)", "@", $html_source);    
     $html_source = str_replace("[at]", "@", $html_source);    
     $html_source = str_replace("(dot)", ".", $html_source);    
     $html_source = str_replace("[dot]", ".", $html_source);    
     $html_source = strtolower($html_source);    
     $ara = array();    
     if (preg_match_all('/([_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3}))/', $html_source, $data)) {        
         $ara = array_unique($data[1]);    
     }    
     return $ara;    
 }    

Please share your thoughts to improve the function.

Trouble with Facebook Client API

I have working on facebook application development (it's a game named Fighter Jets), and facing some weired problem. I have decided to share my experience here.

Today I tried the post link feature of the facebook API. First I tried the following code:
$facebook->api_client->links_post($user_id, 'http://khaaan.com/','Best. Website. Ever.');
I got it from their API documentation.

I got error using it. It says that 'The url you supplied is invalid'. May be it's invalid. Then I changed the URL to http://www.google.com, which is valid definitely! Still getting the same problem!! WTF!

Then I searched their forum and found that I am not the only victim, some people already faced this problem and one of them solved the problem in the following way:
$facebook->api_client->links_post('http://khaaan.com/','Best. Website. Ever.', $user_id);

Which works! Needed to use the user id as the third parameter, but from the example in the API documentation we see that it's the first parameter.

I really don't understand why the documentation is wrong.

Send email using PHP

Sending emails using a PHP script / program is very easy. Just use the mail function: mail($to, $subject, $body);

Check mail function for details.

There can be some problems if it's not configured properly. Check the installation / configuration page for details.

Count number of elements in array - PHP, Perl, Python

We often need to count the number of elements in an array (or get the size of an array). Here is how to do it in PHP, Perl & Python:

PHP: $items = count($ara);

Perl: my $items = scalar(@ara);, you can also try: my $items = @ara;

Python: items = ara.__len__(). Note that in Python it's called list. List can be used as array.

execute linux command using Perl, Python, PHP

Those who program in Linux often need to execute/run linux commands from programs/scripts.

Using python you can execute linux command is the following way:

import os
os.system('ls -lt')


If you use Perl, you can do it in the following ways:
1. system(mkdir $folder);
2. qw(mkdir $folder);
3. $temp = `mkdir $folder`; #back ticks
4. exec($command);

If you use back ticks or qw, $? will be set if any error occurs. So you can use it like this:

qw(rm $filename);
if($?) {
print STDERR "error deleting file\n";
}


There are also several options available to run linux commands using PHP. Take a look at here for detals: http://us2.php.net/manual/en/ref.exec.php

SimpleXML - simple way to parse XML in PHP

This morning I needed to write a PHP script that parses an XML file. I could do it easily with regular expressions - as I can play very well with regexp :). But I was looking for an easier & simpler way to parse XML using PHP, as I thought there must be a very simple way. And I was right, I found SimpleXML. SimpleXML makes XML processing really simple. Here I give links of some excellent (and simple!) resources of SimpleXML:

• SimpleXML: A very well written and comprehensive article/tutorial.
• SimpleXML Functions: SimpleXML functions list with good examples from php.net
• PHP XML SimpleXML: w3schools tutorial.

SimpleXML will definitely speed up your XML processing speed!