Populate drop-down lists from database using PHP and ajax.

[wradyn]

As an example, my MySQL database has 3 tables: main-area, sub-area, and items. Using PHP I populate my first select-list as follows:
[PHP]<?php
// Create list containing the Main Areas
echo "Select an Area:";

echo "<select name='area_select' id='area_select' onChange='getArea();'>\n";
while ($row = mysqli_fetch_assoc($result))
{
extract($row);
echo "<option value=\'$area_id\'>$name\n";
}
echo "</select>\n";
?>[/PHP]
This displays the list correctly. I have set the onChange to the getArea() function from my ajax script.

            var province = document.getElementById("province_select").value;
var url = "result.php";
request.open("POST", url, true);
request.onreadystatechange = updatePage;
request.send(null);

I am not sure what I should set this function to in order for it to get the sub-areas in the chosen main-area from the database. It must then populate a <div> to contain a second select-list containing these sub-areas.
When I then select the sub-area it should do the same, but this time getting the items available in that sub-areas from the database.

Thanks

[pbmods]

Heya, wradyn. Welcome to TSDN!

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