[Resolved] How do you get both the value and the field name from a drop down list?

BigBadKev

Hi all,

I want to get both the value id and the field value like so..

$man_id = $POST['man_id'];
$man_name = $POST['man_name'];

from this list drop box

$sql_stmt = "SELECT man_id, man_name from manufacturer ORDER BY  man_name ASC;";
echo '<select name = "man_list">';
//$sql_array set earlier, $row man_id and $row man_name both return a result
while($row = mysql_fetch_array($sql_array['result'])) {
  echo '<option value = ' . $row['man_id'] .'>' . $row[man_name] . '</option>';
}
echo '</select>';

is this possible? or can i only get one value by making the option value = $row[man_name]?

thanks in advance

BBK 🙂

ahundiak

You only get back the value data. However, you can store both the id and name in the value and then split it apart.

BigBadKev

Hi,

can I ask how I do this?

BBK 🙂

Weedpacket

Erm, why would you need to do this anyway? You've got the man_id from the value; can't you just use that to look up the man_name?

ahundiak

When building the option list:
$value = $row['man_id'] . ':' . $row['man_name'];
'<option value = ' . $value .'>' . $row['man_name'] . '</option>';

When reading in:
$value = $_POST['man_list'];
list($man_id,$man_name) = explode(':',$value);

BigBadKev

Hi all,

I need the man_id and man_name to insert into another table so wanted to grab both from the select list to insert into the table.

BBK 🙂

BigBadKev

cool thanks for the replies I will try this

BBK

Weedpacket

Originally posted by BigBadKev
I need the man_id and man_name to insert into another table so wanted to grab both from the select list to insert into the table.

But that doesn't answer my question: Why do you need to do this? If you've got the man_id is that not enough to find out what the man_name is as well? Are there different man_names with the same man_id? Can the form processing page not look at the same database as the form generating page?

One reason for asking is because you're trusting the user not to send you mismatched man_id and man_name pairs, which they're perfectly capable of doing.

BigBadKev

Hi Weed,

I see the confusion now, I am using man_id as a index with man_name as the name to select so the drop down list index will be exactly as entered into the DB table.

Here is the "other" code for man_id and man_name

$sql->tran_begin();
$sql_stmt = null;
$sql_stmt = "INSERT INTO model (model_id, model_name, manufacturer_man_name, manufacturer_man_id,  model_year, model_version, model_delete, vehicle_type)" .
		                      " VALUES ('null', '$model_name', '$man_name', $man_id,  '$year_list', 'null', 'false', '$vehicle_type[$vehicle_type_list]');";
$sql->sql_execute($sql_stmt);
if ($sql_array["sql_status"]) {
  $sql->tran_commit();
  $d->x("model inserted into DB");
}
else {
  $sql->tran_rollback();
}

I am interested in your reply as I know you are a good programmer so is this ok?

BBK 🙂

Weedpacket

Well, I was thinking that if each man_id applied to exactly one man_name, then getting the man_name from the form won't tell you anything you don't already know; it would be more reliable to take the given man_id from the form and look up the corresponding man_name in the database; use man_id for the values of the dropdown and use man_name only for the human-readable part of the dropdown.

Of course, if each man_id really does only go with exactly one man_name, you don't need to re-store man_name in the model table either, as doing so just duplicates information you already have (any time you do need to know the name, you can just take the id back to the database and ask for the correspnding name).

Just as for the dropdowns, duplicating information generally increases the risk of "duplicates" not matching each other after all - for one reason or another (e.g., people who think it amusing to mangle form fields to send back stupid data, or a manufacturer changes its name) - leading to inconsistent results later on.

BigBadKev

Hi Weed,

The man_id and man_name are foriegn keys in my model table, I am building a car parts system.

I was going to do what you suggested but thought I might as well
just grab both values as in essence its the same data just grabbed all at once.

If you want to see the file I would appreciate any advice so just let me know.

BBK 🙂