PHP - Check if one of two form fields is filled? - php

Question

My form has Phone and Email fields.
Many people might not be wanting/able to put both,
so I thought, that the validator would require only
one of those two filled, instead of requiring the both filled.
I've tried thinking of different ways to do it but I'm pretty new to PHP,
so I couldn't come with any.
Would this be possible?
if ($_SERVER["REQUEST_METHOD"] == "POST")
{
if (empty($_POST["name"]))
{$nameErr = "Name is required";}
else
{$name = test_input($_POST["name"]);}
if (empty($_POST["email"]))
{$emailErr = "Email is required";}
else
{$email = test_input($_POST["email"]);}
if (empty($_POST["phone"]))
{$phone = "";}
else
{$website = test_input($_POST["website"]);}
if (empty($_POST["comment"]))
{$comment = "";}
else
{$comment = test_input($_POST["comment"]);}
}
Thank you.

Answer 1

As your title states, 1 / 2 form fields is filled in.
$i = 0; // PUT THIS BEFORE YOUR IF STATEMENTS
Inside of your statements:
if (empty($_POST["phone"])) {
$phone = "";
} else {
$i++; // PUT THIS IN ALL YOU WANT TO COUNT, IT WILL ADD 1 to $i EACH TIME YOU CALL IT
$website = test_input($_POST["website"]);
}
Now at the end, if
// YOU NEED TO CHANGE YOUR NUMBERS TO WHATEVER COUNT YOU WANT
if ($i < 2) { // IF $i IS LESS THAN 2
// YOUR CODE HERE
} else { // IF $i IS 2 OR MORE
// YOUR CODE HERE
}
Hope this is somewhat useful!
or as stated above, you can use an
if (#$A && #$B) { // REQUIRES BOTH TO BE TRUE
// YOUR CODE HERE
} elseif (#$A || #$B) { // REQUIRES ONLY ONE TO BE TRUE
// YOUR CODE HERE
} else { // NONE ARE TRUE
// YOUR CODE HERE
}
if you are wondering about the # signs above, they are simply checking if they are set, you could change the code to !empty($A) which is what you used above. Putting the ! before the empty function checks that it is false or that $A is actually set.

Answer 2

If i would have to check a form like you, i'd do it this way:
$res = '';
if(empty($_POST['name']))
$res .= 'The name is required.<br>';
if(empty($_POST['email']))
$res .= 'The email is required.<br>';
if(empty($_POST['phone']) && empty($_POST['email']))
$res .= 'You need to enter phone or email.<br>';
if(strlen($res) > 0) {
echo 'We have these errors:';
echo $res;
}
else {
echo 'No Errors!';
}
If you want to show only one error each time, use this code:
$res = '';
if(empty($_POST['name']))
$res = 'The name is required.<br>';
elseif(empty($_POST['email']))
$res = 'The email is required.<br>';
elseif(empty($_POST['phone']) && empty($_POST['email']))
$res = 'You need to enter phone or email.<br>';
if(strlen($res) > 0) {
echo $res;
}
else {
echo 'No Error!';
}
Even if i think it's very basic, i'll explain the mentioned part, even if you could look it up from php.net:
$res .= 'The name is required';
The ".=" operator adds the part 'The name is required' to the variable $res. If this happens the first time, the variable will be empty, because i initialized it as an empty string. With every ongoing line, another error Message will be added to the string.
if(strlen($res) > 0) {
strlen() will return the length of the string in $res. If no error occured, it would still be empty, so strlen() would return 0.