Super-Simple Wordpress RSS Syndication For Your Site

If you’re like me you probably have a blog as well as another site. I have found that an effective way to get vistiors to the blog is to link to it from the main site, assuming that that site is more popular. RSS (Really Simple Syndicate) is a way of syndicating your blog to other areas of the web. It is based on XML and generated automatically by Wordpress.

A PHP RSS parser is MagpieRSS. We will be using it in the following tutorial.

1. Download the most recent version of MagpieRSS from the above website.
2. Upload the “rss” folder to your web server.
3. Next we need to make a PHP include file for displaying the posts. Use the following code

   <?php
   require_once('rss/rss_fetch.inc'); //Include the MagpieRSS include file
   $url = 'http://yoursite.com/blog/?feed=rss2'; //Set a variable containing the URL to your blogs RSS feed
   $rss = fetch_rss($url); //Retrieve the posts
   $items = array_slice($rss->items, 0, 5); //Only show the first 5 posts (the second number can be customized to suit your needs)
   $posts = '';
   foreach ($items as $item) { //Loop through the items
   	$href = $item['link'];
   	$cat = $item['category'];
   	$title = $item['title'];
   	$date = $item['pubdate'];
   	$text = $item['content']['encoded'];
   	$text = preg_replace('/<img [^>]+\/?>/', '[image]', $text); //Replace images with [image]
   	$text = preg_replace('/<\/?[^>]+>/', '', $text); //Get rid of HTML
   	$posts .= "<li><a href=$href>$title</a> <em>".substr($text, 0, 100)."</em></li>"; //Print the current post title linked to the page on your blog, and the first 100 chars of the post
   }
   echo $posts;
   ?>

4. Now you can include that file into your site wherever you want the feed to appear. Enjoy the free traffic!

How to Catch Hackers, Pt. 2

if(stristr($_GET['p'], 'order by') || stristr($_GET['p'], '--') || stristr($_GET['p'], '\'') || stristr($_GET['p'], '../'))
{
		echo '
No Script Kiddies Allowed

Checking user IQ...
User IQ < minimum. Page not loaded.
Sending e-mail to webmaster (I\'m not kidding)...
Success!
If you want to hack this page, please type the following in a terminal: sudo rm -rf /';
		$text = 'IP Address: '.$_SERVER['REMOTE_ADDR'].'
Query string: '.$_GET['p'];
		mail('you@gmail.com', 'SQL Hacker', $text, "From: you@gmail.com\n");
}

This does not actually protect your site, if you’re using SQL you should properly escape your input. This site uses flatfiles so it’s interesting how many people try an SQL injection (3 so far) — but since I put this up they always leave after the first attempt!

Update (8/10): I forgot the most important part of the code… fixed now >_<

Keep Spambots Out with a Simple Math CAPTCHA

Spambots are undoubtably among the most annoying problems for web developers. They look for forms on your site, and submit links to their own websites, repeated many times and mixed with keywords. One way to deter them is a CAPTCHA (Completely Automated Public Turing Test to Tell Computers and Humans Apart). One common form of this is an image with distorted letters, and the user has to type in the letters. I find those really annoying, and unless you are very popular you probably don’t need something so difficult to crack. Our CAPTCHA will ask the user to answer an addition problem.
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Pagination in PHP

If you are going to have a site where users can submit stuff, and the stuff is listed on one page, you definitely need pagination. Pagination scripts consist of two main parts: getting the correct records and displaying them, and displaying the page links at the bottom.
More »

Some Random PHP Functions

Please use these

Math Functions:

function distance($x1, $y1, $x2, $y2)
{
	$x = pow($y2 - $y1, 2);
	$y = pow($x2 - $x1, 2);
	$distance = sqrt($x + $y);
	return $distance;
}
function midpoint($x1, $y1, $x2, $y2)
{
	$x = ($x1 + $x2)/2;
	$y = ($y1 + $y2)/2;
	$midpoint = '('.$x.','.$y.')';
	return $midpoint;
}
function calculate($equation)
{
	$equation = ereg_replace('([A-Z]|[a-z])', '', $equation);
	$answer = eval('return '.$equation.';');
	return $answer;
}

String Functions:

function array_stristr($text, $search)
{
    $num_matches = 0;
    for($i = 0; $i < count($search); $i++)
    {
        if(stristr($text, $search[$i]))
        {
            $num_matches++;
        }
    }
    return $num_matches;
}
function get_words($text, $offset, $length=null)
{
	$text = explode(' ', $text);
    if($length)
        $text = array_slice($text, $offset, $length - $offset + 1);
    else
        $text = array_slice($text, $offset);
    $text = implode(' ', $text);
    return $text;
}

Text Functions:

function alternating_caps($text)
{
	$text = strtolower($text);
	$x = 1;
	for($i = 0; $i < strlen($text); $i++)
	{
		if($x == 1)
		{
			$text{$i} = strtoupper($text{$i});
			$x = 2;
		}
		elseif($x == 2)
		{
			$x = 1;
		}
	}
	return $text;
}
function random_caps($text)
{
	$text = strtolower($text);
	for($i = 0; $i < strlen($text); $i++)
	{
		$x = round(rand(0, 1));
		if($x == 1)
		{
			$text{$i} = strtoupper($text{$i});
		}
		elseif($x == 2)
		{
		}
	}
	return $text;
}

Hopefully these will be useful for somebody.

How To Catch Hackers

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