For this article, let's pretend you have the following database table. There are two columns (I'm separating the fields with commas for readability), Item and Price:
Cheese Pizza, 1.00
Pepperoni Pizza, 1.50
Sausage Pizza, 1.50
Cheese Calzone, 1.50
Ham Calzone, 2.00
What if you want to populate a combo-box with your possible options? We can write php that generates a drop-down box that has five item choices in it, based on our table above. Here is the sample code:
<?php
// Connect to the database
mysql_connect("localhost", "user", "password") or die(mysql_error());
mysql_select_db("name") or die(mysql_error());
// Has the form been submitted?
if (isset($_POST['item'])) {
// The form has been submitted, query results
$queryitem = "SELECT * FROM table WHERE item = '".$_POST['item']."';";
// Successful query?
if($result = mysql_query($queryitem)) {
// More than 0 results returned?
if($success = mysql_num_rows($result) > 0) {
// For each result returned, display it
while ($row = mysql_fetch_array($result)) echo $row[serial];
}
// Otherwise, no results, tell user
else { echo "No results found."; }
}
// Error connecting? Tell user
else { echo "Failed to connect to database."; }
}
// The form has NOT been submitted, so show the form instead of results
else {
// Create the form, post to the same file
echo "<form method='post' action='example.php'>";
// Form a query to populate the combo-box
$queryitem = "SELECT DISTINCT item FROM table;";
// Successful query?
if($result = mysql_query($queryitem)) {
// If there are results returned, prepare combo-box
if($success = mysql_num_rows($result) > 0) {
// Start combo-box
echo "<select name='item'>n";
echo "<option>-- Select Item --</option>n";
// For each item in the results...
while ($row = mysql_fetch_array($result))
// Add a new option to the combo-box
echo "<option value='$row[item]'>$row[item]</option>n";
// End the combo-box
echo "</select>n";
}
// No results found in the database
else { echo "No results found."; }
}
// Error in the database
else { echo "Failed to connect to database."; }
// Add a submit button to the form
echo "<input type='submit' value='Submit' /></form>";
}
?>
