Error on invalid variable

nic0las

Hi,

I'm wondering if there is any way to redirect the user or display a message if the variables defined in the url are invalids.

I mean, if somebody comes to my site using bad parameters in the url (say, "http://www.domain.tld/index.php?news=54", the 54th news being non existent), he gets the structure of the page, whitout having its content. Well, no further explanations are needed, since all php users noticed that..

Thanks for your ideas.

yelvington

Of course there is; you just have to write the necessary code. Whether you emit an error message or a redirect header is entirely up to you.

nic0las

This is not the reply I expected. In fact, I misformulated my question...

mykg4orce

yelvington is right. Error handling can be the most extensive coding job on any site. Depending on how many variables you ar passing can determine this.

For example '?news=54' does not exist.

Well if this news is being read from a DB, then you can simply add a few lines on code to your existing result to see if the news ID exists or not.

require('admin/mysql_config.php');  

$dbconn = mysql_connect("localhost", "$dbuser", "$dbpassword")
		or die();
$result = mysql_select_db("$dbname", $dbconn)
		or die();

$query = "SELECT * FROM table";
$result = mysql_db_query("$dbname", $query);

if ($result) {		
$numOfRows = mysql_num_rows($result);
if ( $numOfRows < "1" ) {
//this is where you do your error handling:
//this would determine that there is no row by the id '54'
echo "The requested id does not exist!";
echo "<META HTTP-EQUIV=\"refresh\" content=\"5; URL=redirect_url.php\">";
} else {
for ($i = 0; $i < $numOfRows; $i++){
$news_id = mysql_result ($result, $i, "news_id");
//echo your results
}
}