Question

I would like to ask help on how and what is the best way to handle this kind of scenario, for me its too complex. maybe example is highly appreciated.

the page that i want to build should have this features.

1. can be open in browser via http://server/view.php?id=1000
2. if id=1000 does not exist, post a message not exist and throw it to another page
3. if id=1000 does exist, then open the page for viewing
4. the page has a form with with a textbox where i can add info about the records
5. the form submit to itself and process the data to DB.

how can i combine all these since features? i really appreciate if a sample snippet code especially on the form submit, checking if id exist thanks a lot.

Answer 1

Very basic example below. You can fill in the details

$id = intval($_GET['id']);  // assume it's int and force to be int

// do database call
// 1. init connection, set db, etc
mysql_query("select something from something where id = ".$id);

// check for results
if (! results exist) http_redirect('your error page');

// Now check if any posted variables exist
if (isset($_POST['field1']) && isset($_POST['field=2']) .... 
{
   1. validate your data
   2. insert to the database
   3. http_redirect to success page
}

// if you're getting here, that means id is valid and data has not been posted
 show your form
 display whatever HTML you need with the data loaded for id above