Option list which can retrieve from and post to database - php

Question

can anybody post an code for option list which can retrieve data dynamically from database, and once user selects from option list a record, that record must post it ($_POST) to database.. !!
ive tried this, it retrieves records from db, but not posting it :
<?php
require_once "db.php";
if (isset($_POST['a_id']) {
$a = $_POST ['a_id'];
$sql = "INSERT INTO projektet
VALUES ('$a')";
mysql_query($sql);
}
HERE IS THE PART SEEMS NOT WORKING :
<form method="post">
<select name="a_id">
<?php
$host="localhost";
$username = 'root';
$password = "";
$con = mysql_connect($host,$username,$password);
mysql_select_db('naho',$con);
// Checking connection
if (!$con){
echo ("Failed to connect to MySQL:. " .mysql_error($con));
}
else {
echo("db connect");
}
$result = mysql_query("SELECT * from `arqitekti`");
if($result == FALSE) {
die(mysql_error()); // TODO: better error handling
}
while($row=mysql_fetch_array($result)){
?>
<option value="<?php '.row[a_id];'?>"><?php echo $row["a_emri"];?></option>
<?php }
?>
</select>
<input type="submit" value="submit"/>
</form>

Answer 1

<option value="<?php '.row[a_id];'?>"><?php echo $row["a_emri"];?></option>
This line looks strange... Shouldn't it be:
<option value="<?php echo $row[a_id]; ?>"><?php echo $row["a_emri"];?></option>
I think that your code is POSTing, but it wasn't getting any value because of the value declaration on the options of the select. After that change it should work.
PS: If your POST code isn't in the same page as your HTML, it's <form method="POST" action="YOUR_PAGE">, not only <form method="POST">.