PHP: check if any posted vars are empty - form: all fields required

Question

Is there a simpler function to something like this:

if (isset($_POST['Submit'])) {
    if ($_POST['login'] == "" || $_POST['password'] == "" || $_POST['confirm'] == "" || $_POST['name'] == "" || $_POST['phone'] == "" || $_POST['email'] == "") {
        echo "error: all fields are required";
    } else {
        echo "proceed...";
    }
}

score 82 · Accepted Answer · answered Jul 06 '10 at 21:46

82

Something like this:

// Required field names
$required = array('login', 'password', 'confirm', 'name', 'phone', 'email');

// Loop over field names, make sure each one exists and is not empty
$error = false;
foreach($required as $field) {
  if (empty($_POST[$field])) {
    $error = true;
  }
}

if ($error) {
  echo "All fields are required.";
} else {
  echo "Proceed...";
}

answered Jul 06 '10 at 21:46

Harold1983-

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3

Again, I recommend an isSet($_POST[$field]). This is a good solution, though. – Borealid Jul 06 '10 at 21:47
9

empty() checks for both existance, and non false-ish values (null, false, 0, empty string). – Harold1983- Jul 06 '10 at 21:48
Almost the same as my approach. However I'm stuck with the "Proceed" part. You assumed that everything is required, so it's all go or no go. But what if some aren't. Do I have to check once again for each and every $_POST if they are empty so I can sql them to database? I feel bad loop checking for all $_POST twice. Or is that just how it usually is? A newbie here...help please? – Fred Nov 08 '12 at 14:49
or instead of the $required array, u can directly use `foreach($_POST as $field => $ignore_value)` – Osa Apr 16 '13 at 22:33
2

This `foreach` will only validate the last value of `array` (which is email) as it overrides the previous `$error` validation. – Nimitz E. Aug 28 '15 at 07:58
7

@NimitzE. not necessarily. `$error` is set to false, and only when a field is empty is it changed. It doesn't matter which field throws it, because once its thrown, its thrown. i.e. if `name` was empty, it would run `false, false, false, true, false, false` but as there's no `else` in the `if`, `$error` is now `true`. – MLMLTL Apr 07 '16 at 10:15
2

Just be careful if 0 is an acceptable value for a required field. As @Harold1983- mentioned, these are treated as empty in PHP. Better to use isset – accord_guy Nov 28 '17 at 20:55
Right said by @NimitzE.better declare an empty array for `$errors = array()` and use `array_push()` function and check for `empty($errors)`. if `$errors` array is empty then it means loop processing was successful. – Muhammad Tarique Nov 16 '19 at 09:08

score 5 · Answer 2 · edited Sep 18 '12 at 21:58

5

if( isset( $_POST['login'] ) &&  strlen( $_POST['login'] ))
{
  // valid $_POST['login'] is set and its value is greater than zero
}
else
{
  //error either $_POST['login'] is not set or $_POST['login'] is empty form field
}

edited Sep 18 '12 at 21:58

Jeremy J Starcher

23,369
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answered Sep 18 '12 at 21:54

Nahser Bakht

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if you have an empty field submitted then the strlen() evaluates to 0 which is false in PHP. – Nahser Bakht Sep 18 '12 at 21:59
This is the better answer if the `0` value is meaningful – Nick Apr 26 '21 at 08:30

score 3 · Answer 3 · answered Jul 06 '10 at 21:50

I use my own custom function...

public function areNull() {
    if (func_num_args() == 0) return false;
    $arguments = func_get_args();
    foreach ($arguments as $argument):
        if (is_null($argument)) return true;
    endforeach;
    return false;
}
$var = areNull("username", "password", "etc");

I'm sure it can easily be changed for you scenario. Basically it returns true if any of the values are NULL, so you could change it to empty or whatever.

Jacob Relkin · Answer 4 · 2010-07-06T21:49:31.610

2

empty and isset should do it.

if(!isset($_POST['submit'])) exit();

$vars = array('login', 'password','confirm', 'name', 'email', 'phone');
$verified = TRUE;
foreach($vars as $v) {
   if(!isset($_POST[$v]) || empty($_POST[$v])) {
      $verified = FALSE;
   }
}
if(!$verified) {
  //error here...
  exit();
}
//process here...

edited Jul 06 '10 at 21:49

answered Jul 06 '10 at 21:44

Jacob Relkin

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You also need an isSet, I think - otherwise you'll get an error if the value wasn't posted at all. – Borealid Jul 06 '10 at 21:45
5

`empty()` does the whole job, no need to call `isset()` it's redundant logic. – mickmackusa Jun 29 '18 at 03:09

score 1 · Answer 5 · answered Mar 05 '23 at 12:05

1

if (array_filter(["param1", "param2", "param3"],
    fn(string $param) => !array_key_exists($param, $_POST))) {
        throw new Exception('Missing element');
}

answered Mar 05 '23 at 12:05

Mustafa Özyurt

26
3

Calin Rusu · Answer 6 · 2013-11-04T00:19:08.873

0

I did it like this:

$missing = array();
 foreach ($_POST as $key => $value) { if ($value == "") { array_push($missing, $key);}}
 if (count($missing) > 0) {
  echo "Required fields found empty: ";
  foreach ($missing as $k => $v) { echo $v." ";}
  } else {
  unset($missing);
  // do your stuff here with the $_POST
  }

edited Nov 04 '13 at 00:19

answered Nov 04 '13 at 00:03

Calin Rusu

49
3

Why you're echoing $v if it's deliberately empty? Also, this code doesn't check for *missing* fields. Also, it's prone to CSS – Your Common Sense Mar 05 '23 at 12:10

score -1 · Answer 7 · answered Feb 03 '15 at 00:41

I just wrote a quick function to do this. I needed it to handle many forms so I made it so it will accept a string separated by ','.

//function to make sure that all of the required fields of a post are sent. Returns True for error and False for NO error  
//accepts a string that is then parsed by "," into an array. The array is then checked for empty values.
function errorPOSTEmpty($stringOfFields) {
        $error = false;
            if(!empty($stringOfFields)) {
                // Required field names
                $required = explode(',',$stringOfFields);
                // Loop over field names
                foreach($required as $field) {
                  // Make sure each one exists and is not empty
                  if (empty($_POST[$field])) {
                    $error = true;
                    // No need to continue loop if 1 is found.
                    break;
                  }
                }
            }
    return $error;
}

So you can enter this function in your code, and handle errors on a per page basis.

$postError = errorPOSTEmpty('login,password,confirm,name,phone,email');

if ($postError === true) {
  ...error code...
} else {
  ...vars set goto POSTing code...
}

score -1 · Answer 8 · answered Dec 27 '17 at 09:22

Note : Just be careful if 0 is an acceptable value for a required field. As @Harold1983- mentioned, these are treated as empty in PHP. For these kind of things we should use isset instead of empty.

$requestArr =  $_POST['data']// Requested data 
$requiredFields = ['emailType', 'emailSubtype'];
$missigFields = $this->checkRequiredFields($requiredFields, $requestArr);

if ($missigFields) {
    $errorMsg = 'Following parmeters are mandatory: ' . $missigFields;
    return $errorMsg;
}

// Function  to check whether the required params is exists in the array or not.
private function checkRequiredFields($requiredFields, $requestArr) {
    $missigFields = [];
    // Loop over the required fields and check whether the value is exist or not in the request params.
    foreach ($requiredFields as $field) {`enter code here`
        if (empty($requestArr[$field])) {
            array_push($missigFields, $field);
        }
    }
    $missigFields = implode(', ', $missigFields);
    return $missigFields;
}

score -1 · Answer 9 · answered Aug 13 '19 at 18:21

-1

foreach($_POST as $key=>$value)
{

   if(empty(trim($value))
        echo "$key input required of value ";

}

answered Aug 13 '19 at 18:21

dılo sürücü

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I do not understand how does this answer the question? – Dharman Aug 13 '19 at 18:49
if empty any $_POST key handle it and give message – dılo sürücü Aug 13 '19 at 19:43
1

Handle what exactly? You are checking random values. The question is about validating mandatory input. – Dharman Aug 13 '19 at 19:44
@Dharman the question is about having **all** fields filled out, so I don't see how this solution should be completely wrong – Nico Haase Aug 14 '19 at 08:43
What if POST is empty? What if I do not submit any data? Your validation will accept it because the foreach loop will not be executed. – Dharman Aug 14 '19 at 08:44

score -2 · Answer 10 · answered Jul 06 '10 at 21:45

-2

Personally I extract the POST array and then have if(!$login || !$password) then echo fill out the form :)

answered Jul 06 '10 at 21:45

Doug Molineux

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Awww, always a dangerous practice, because it may be possible to smuggle global variables into your script through `$_POST`. – Pekka Jul 06 '10 at 21:48
I've heard something about this before, and its probably not the best way to go :) especially if its something important – Doug Molineux Jul 06 '10 at 21:56

PHP: check if any posted vars are empty - form: all fields required

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