PHP Form for required Fields - php

Question

I have a basic Form that submits data into a database and I want it to require certain fields to be submitted, so far it recongizes that the fields are empty, but it still submits regardless. I can't seem to find a solution..
Code
<?
// define variables and set to empty values
$asinErr = $qtyErr = $floorErr = $locErr;
$asin = $quantity = $floor = $location;
# this is processed when the form is submitted
# back on to this page (POST METHOD)
if ($_SERVER['REQUEST_METHOD'] == "POST")
{
if (empty($_POST["asin"]))
{$asinErr = "ASIN is required";}
else
{$asin = addslashes($_POST["asin"]);}
if (empty($_POST["quantity"]))
{$qtyErr = "Quantity is required";}
else
{$quantity = addslashes($_POST["quantity"]);}
if (empty($_POST["floor"]))
{$floorErr = "Floor is required";}
else
{$floor = addslashes($_POST["floor"]);}
if (empty($_POST["location"]))
{$locErr = "Location is required";}
else
{$location = addslashes($_POST["location"]);}
# setup SQL statement
$sql = " INSERT INTO kiva_amnesty_log ";
$sql .= " (asin, quantity, floor, location, date) VALUES ";
$sql .= " ('$asin','$quantity','$floor','$location', now()) ";
#execute SQL statement
$result = mysql_query($sql, $cid);
# check for error
if (mysql_error()) { print "Database ERROR: " . mysql_error(); }
print "<h3><font color=red>New Amnesty Added - View it <a href=amnesty_log_summary.php>HERE</a></font></h3>";
}
?>
<form name="fa" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>" method="POST">
<table>
<tr><td>ASIN:</td><td><input type="text" name="asin" id="asin"><span class="error">* <?php echo $asinErr;?></span></td></tr>
<tr><td>Quantity:</td><td><input type="text" name="quantity" id="quantity"><span class="error">* <?php echo $qtyErr;?></span></td></tr>
<tr><td>Floor:</td><td><select name="floor"><option value="1">Floor 1</option><option value="2">Floor 2</option></select><span class="error">* <?php echo $floorErr;?></span></td></tr>
<tr><td>KIVA Floor:</td><td><input type="radio" value="Yes" name="location">Yes<input type="radio" value="No" name="location">No</select><span class="error">* <?php echo $locErr;?></span></td></tr>
<tr><td><input type="submit" name="submit" id="submit" value="Submit Amnesty!"></td></tr>
</table>
</form>
Updated:
<?
// define variables and set to empty values
$asinErr = $qtyErr = $floorErr = $locErr = "";
$asin = $quantity = $floor = $location = "";
$lb_error = 0;
if ($_SERVER['REQUEST_METHOD'] == "POST")
{
if (empty($_POST["asin"])) {
$asinErr = "ASIN is required";
$lb_error = 1;
} else {
$asin = addslashes($_POST["asin"]);
}
if (empty($_POST["quantity"])) {
$qtyErr = "Quantity is required";
$lb_error = 1;
} else {
$quantity = addslashes($_POST["quantity"]);
}
if (empty($_POST["floor"])) {
$floorErr = "Floor is required";
$lb_error = 1;
} else {
$floor = addslashes($_POST["floor"]);
}
if (empty($_POST["location"])) {
$locErr = "Location is required";
$lb_error = 1;
} else {
$location = addslashes($_POST["location"]);
}
if($lb_error) {
continue;
}
# setup SQL statement
$sql = " INSERT INTO kiva_amnesty_log ";
$sql .= " (asin, quantity, floor, location, date) VALUES ";
$sql .= " ('$asin','$quantity','$floor','$location', curdate()) ";
#execute SQL statement
$result = mysql_query($sql, $cid);
# check for error
if (mysql_error()) { print "Database ERROR: " . mysql_error(); }

Answer 1

You want to check if you error variables are empty. If they are not, then break the script
ie
if(!empty($asinErr) || !empty($qtyErr) || !empty($floorErr) || !empty($locErr) ) {
break;
}
Something along these lines.
Check for the errors before you get to the point where you are writing to the database

Answer 2

Define at the top
$lb_error = 0;
Throughout your if/else checks for errors, if there is an error, assign the variable a 1
if (empty($_POST["asin"])) {
$asinErr = "ASIN is required";
$lb_error = 1;
} else {
$asin = addslashes($_POST["asin"]);
}
Then after you have completed all of these, do a check for errors and break if there are any
if($lb_error) {
break;
}