CREATE TABLE `articles` ( `ID` int(11) NOT NULL auto_increment, `a_title` varchar(255) NOT NULL, `a_subtitle` tinytext NOT NULL, `a_content` text NOT NULL, PRIMARY KEY (`ID`) ) ENGINE=MyISAM; INSERT INTO `articles` VALUES (1, 'This is the article title', 'This is the article subtitle', 'This is the article content This is the article content This is the article content This is the article content This is the article content '); INSERT INTO `articles` VALUES (2, 'This is the article title', 'This is the article subtitle', 'This is the article content This is the article content This is the article content This is the article content This is the article content '); CREATE TABLE `articles_ratings` ( `ID` int(11) NOT NULL auto_increment, `article_id` int(11) NOT NULL, `rating_value` tinyint(2) NOT NULL, `rater_ip` varchar(20) NOT NULL, PRIMARY KEY (`ID`) ) ENGINE=MyISAM;Our example will be formed from 2 visible pages, one will list the articles and the other one (linked) will display the details. Our rating table will store the value of the rating, the article id (necessary to build the relations and output data/ratings) and also the ip of the visitor. At start, I was thinking to allow only registered members to rate but that would only complicate things. You can adjust the script to require membership. What I like at xajax is the fact that it doesn't needs javascript enabled (it's Unobtrusive), you work only with PHP (no Javascript knowledge required), it's easy to configure and it's free. I will skip the creation of the first page which has nothing important on it but an sql SELECT to pull the articles from the database and link them to the 2nd page which is where we'll stop and show/explain our code.
<?php
require_once("db.php");
require_once("xajax/xajax.inc.php");
require("functions.php");
$xajax = new xajax();
$xajax->registerFunction("insert_rating");
$xajax->processRequests();
$query = mysql_query("SELECT * FROM articles WHERE ID ='".mysql_real_escape_string($_GET['ID'])."'");
echo '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">'."\n";
echo '<html xmlns="http://www.w3.org/1999/xhtml">'."\n";
echo ' <head>'."\n";
echo ' <title>Testing the PHP/Ajax rating script</title>'."\n";
echo ' '.$xajax->printJavascript();
echo ' </head>'."\n";
echo ' <body>';
if(mysql_num_rows($query)==1)
{
$row=mysql_fetch_assoc($query);
echo ' <h1>'.$row['a_title'];
echo '</h1>'."\n";
echo $row['a_content'];
echo ' <hr />'."\n";
echo ' <div id="response">'."\n";
echo ' <table>'."\n";
echo ' <tr>'."\n";
echo ' <td align="center" style="width:50px">1</td>'."\n";
echo ' <td align="center" style="width:50px">2</td>'."\n";
echo ' <td align="center" style="width:50px">3</td>'."\n";
echo ' <td align="center" style="width:50px">4</td>'."\n";
echo ' <td align="center" style="width:50px">5</td>'."\n";
echo ' </tr>'."\n";
echo ' <tr>'."\n";
echo ' <td align="center" style="width:50px"><input type="radio" name="rating" id="radio_1" onclick="xajax_insert_rating(1, '.$_GET['ID'].');" /></td>'."\n";
echo ' <td align="center" style="width:50px"><input type="radio" name="rating" id="radio_2" onclick="xajax_insert_rating(2, '.$_GET['ID'].');" /></td>'."\n";
echo ' <td align="center" style="width:50px"><input type="radio" name="rating" id="radio_3" onclick="xajax_insert_rating(3, '.$_GET['ID'].');" /></td>'."\n";
echo ' <td align="center" style="width:50px"><input type="radio" name="rating" id="radio_4" onclick="xajax_insert_rating(4, '.$_GET['ID'].');" /></td>'."\n";
echo ' <td align="center" style="width:50px"><input type="radio" name="rating" id="radio_5" onclick="xajax_insert_rating(5, '.$_GET['ID'].');" /></td>'."\n";
echo ' </tr>'."\n";
echo ' </table>'."\n";
echo ' </div>'."\n";
}
else {
echo 'There are no articles to display';
}
echo ' </body>';
echo '</html>';
?>
At the beginning of our code (besides the fact that I included function.php and db.php for the script to work) you will notice that I created a new xajax object $xajax and registered a function (insert_rating) which is located in functions.php. Xajax requires you to register the functions you will work with on the page so it can generate the javascript lines ($xajax->printJavascript()) needed to communicate with it's core. Our function (insert_rating) does a very simple task. It first runs a little check to see if the visitor that wishes to insert a new vote has already voted and if the result is FALSE it will insert the rating. Either way, it returns with a result using an element id (<div id="response">) of our choice ($objResponse->addAssign("response","innerHTML", $response));. I used a div which also holds the rating table because it's unnecessary to show our rating system once the vote has been stored and the response sent back. For our little example we used "addAssign" but xajax is also able to return alerts "addAlert", to do redirects and a lot more.
function insert_rating($rating, $article_id)
{
if(mysql_num_rows(mysql_query("SELECT ID FROM articles_ratings
WHERE rater_ip='".mysql_real_escape_string(getIP())."'
AND ID='".mysql_real_escape_string($article_id)."'"))==0)
{
if(mysql_query("INSERT INTO articles_ratings
(`article_id`, `rating_value`, `rater_ip`)
VALUES ('".mysql_real_escape_string($article_id)."',
'".mysql_real_escape_string($rating)."',
'".mysql_real_escape_string(getIP())."')"))
{
$response = 'Thank you for voting this article!';
}
else {
$response = 'Ups. A problem. I was unable to save your rating!';
}
}
else {
$response = 'Sorry but you can only rate once';
}
$objResponse = new xajaxResponse();
$objResponse->addAssign("response","innerHTML", $response);
return $objResponse;
}
As you can see in our function above, it works with two parameters: the value of the rating and the article id. Those values will be specified in our html part with an onClick event applied to a checkbox:
<input type="radio" name="rating" id="radio_4" onclick="xajax_insert_rating(4, '.$_GET['ID'].');" />You will also notice some other functions in our examples (for more functions and code snippets please visit pur snippets section) needed to a better retrieval of the visitors ip address. Everything else is self explanatory. You may download the full example lower on the page.
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Ajax/PHP rating script Archive containing the Ajax/PHP rating script files Uploaded on: 2007-09-21 | 01:02 am |
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2009-06-14 | 02:45 am
2009-06-02 | 07:34 am
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