Checkbox woes: passing multiple values to MySQL query

[walterbennet]

This is my very first PHP project, aside from tests I've executed in manuals. That being the case, I'm sure the solution will be apparent to experienced users, however it's not so apparent that I could find the solution with a thorough browsing of these forums and the internet at large.

The idea is to limit the TYPE of data that is ultimately presented in a list. My real problem is figuring out how to incorporate multiple search types in the MySQL SELECT string (see end of post), while taking the WHERE clauses from the checkboxes. As I understand it, I need a && between each result.

Anyway, here's the lovely form. There are three classes to each entry, and users can select whichever combination of the three they'd like. The fourth option in the form is to enable all the types.

<form action="test-j9c9e.php" method="get">
<ul>
<p><input type="checkbox" name="form_class" value="1"/>Strictly Legitimate kills, please.</p>
<p><input type="checkbox" name="form_class" value="2"/>Include Indeterminate kills.</p>
<p><input type="checkbox" name="form_class" value="3"/>Include Miscellanous kills.</p>
<p><input type="checkbox" name="form_class" value="4"/>Show me everything. </p>
</ul>

Once the values are passed to PHP, I've tried two functions to parse the data into its a usable format, neither of which I'm confident are 100% syntactically correct. I first tried a series of IF statements, but learned that they will simply bypass the remainder of the statements once they encounter a true statement. This does not work since I need users to be able to select MULTIPLE types.

if ($form_class = 1) {
$type = "'legitimate'";}

elseif ($form_class = 2) {
$type = "'indeterminate'";}

elseif ($form_class = 3) {
$type = "'miscellaneous'";}

elseif ($form_class = 4) {
$type = "'legitimate' && 'indeterminate' && 'miscellaneous'";}

elseif ($form_class = 1 && $form_class = 2) {
$type = "'legitimate' && 'indeterminate'";}

elseif ($form_class = 1 && $form_class = 3) {
$type = "'legitimate' && 'miscellaneous'";}

elseif ($form_class = 2 && $form_class = 3) {
$type = "'indeterminate' && 'miscellaneous'";}

elseif ($form_class = 1 && $form_class = 2 && $form_class = 3) {
$type = "'legitimate' && 'indeterminate' && 'miscellaneous'";}

And, a somewhat unwieldy switch(), which doesn't seem to work at all for the format...

switch($form_class) 
{ 
	case "1" : $type = 'legitimate';
	case "2" : $type = 'indeterminate'; 
	case "3" : $type = 'miscellaneous';
	case "4" : $type = "'legitimate' && 'indeterminate' && 'miscellaneous'"; break;

}

And here we run into the brick wall. The syntax from the results of the IF/Switch statements don't compute with the MySQL query as is...:

$query="SELECT * FROM roster WHERE classs = $type";

Thanks in advance!

PS: And yes, I'm aware 'classs' is not supposed to have 3 s's. However, I couldn't get it to work as 'class' The data is reads from the MySQL database also reads as 'classs' so, it's merely superficial.

[laserlight]

Firstly, since you use checkboxes instead of radio buttons, the form elements must result in an array. Also, you should (or rather might as well) use method="post" instead of method="get".

<form action="test-j9c9e.php" method="post"> <ul> <p><input type="checkbox" name="form_class[]" value="1"/>Strictly Legitimate kills, please.</p> <p><input type="checkbox" name="form_class[]" value="2"/>Include Indeterminate kills.</p> <p><input type="checkbox" name="form_class[]" value="3"/>Include Miscellanous kills.</p> <p><input type="checkbox" name="form_class[]" value="4"/>Show me everything. </p> </ul>

Now, check that $POST['form_class'] exists and is an array. After that, construct an array of the values to search for in the SQL statement.

if (isset($_POST['form_class']) && is_array($_POST['form_class'])) {
	$class_types = array();
	if (in_array('4', $_POST['form_class'])) {
		$class_types = array("'legitimate'", "'indeterminate'", "'miscellaneous'");
	} else {
		if (in_array('1', $_POST['form_class'])) {
			$class_types .= "'legitimate'";
		}
		if (in_array('2', $_POST['form_class'])) {
			$class_types[] = "'indeterminate'";
		}
		if (in_array('3', $_POST['form_class'])) {
			$class_types[] = "'miscellaneous'";
		}
	}

if (count($class_types) > 0) {
	// need a string from the array
	$class_types = implode(',', $class_types);
	$query = "SELECT * FROM roster WHERE classs IN ($class_types)";
	// run the query etc
	// ...
} else {
	// no valid class types selected
}
} else {
	// no class types selected
}

[walterbennet]

Edit: Fixed it. There were some brackets you left out by accident in oneof the IF statements. But, now it all works like it's supposed to. Thank you so very much for your quick and helpful response!

Whew... that solution was frankly waaay over my head. I feel like I'm in deep water at this point, with so many more functions to finalize... You just may hear from me again 🙂

[laserlight]

oops, I originally planned on it being a string, but later switched to an array but forgot to change one of the lines.

Change:

if (in_array('1', $_POST['form_class'])) {
	$class_types .= "'legitimate'";
}

to

if (in_array('1', $_POST['form_class'])) {
	$class_types[] = "'legitimate'";
}