How do you collect input from a <select> form? - php

Question

I'm creating a page using HTML and PHP that accesses a Marina database(containing boats/owners ETC...), but I dont know how to capture and use the choice selected from the drop down <select> form and then display all the boats under that owners name(on the same page).
Here is my relevant code...
echo '<form align="left"; top="200"; action="page2.php"; method="post">
<p>Select an owner:</p>
<select top="200"; name="form1"; id="form1">';
foreach($values as $v){
echo '<option value="'.$v['LastName'].'">'.$v['LastName'].'</option>';
}
echo '</select>
</form>
<form align="left"; top="250">
<input type="submit" value="Submit">
</form>';
$form1 = $_REQUEST['form1'];
if($form1){//if there is data submitted to the page
echo '<p>$form1</p>';
}
When I use this code I get an error stating "form1 is an undefined index"
My question is how would I capture the name chosen as a variable from the drop down list when the submit button is clicked? (I apologize as I am very new to HTML and PHP and am only posting here because I cannot find a simple or clear answer anywhere else)

Answer 1

The problem is your <input type="submit"> is not part of the same form. Because you create an independent form for the submit button, it only submits that independent form. This independent form does not have the name attribute set, so your $_REQUEST['form1'] will indeed be undefined.
To correct this, simply have the one form, which contains both the selection and submission:
echo '<form align="left" top="200" action="page2.php" method="post">
<p>Select an owner:</p>
<select top="200" name="form1" id="form1">';
foreach($values as $v){
echo '<option value="'.$v['LastName'].'">'.$v['LastName'].'</option>';
}
echo '</select>
<input type="submit" value="Submit">
</form>';
$form1 = $_POST['form1'];
if($form1){ // if there is data submitted to the page
echo '<p>$form1</p>';
}
Note that you also shouldn't have the semicolons separating the HTML attributes; I've removed these. You'll also really want to use $_POST instead of $_REQUEST, as you don't want $_GET access. I've changed this as well.
You also might want to consider extracting the logic from your markup, and separating the two out.