Check if multiple strings are empty [duplicate]

Another possibility:

$elements = array($name, $email, $mobile);
$valid = true;

foreach ($elements as $element) {
    if (empty($element)) {
        $valid = false;
    }
}

if ($valid) {
    // complete
} else {
    // alert! some element is empty
}

Something like this?

foreach($_POST as $key => $value) 
{
    if (empty($_POST[$key]))
    {
        echo '<div class="empty_p">'.$_POST[$key].' is empty.</div>';
    }
}

It's good to be specific about where this data should be expected, e.g. $_POST:

if (!isset($_POST['name'], $_POST['phone'], $_POST['email'], $_POST['mobile'], $_POST['state'], $_POST['street'], $_POST['city'])) {
    // something is up
}

You can shorten this code a little bit by creating an array with your required field names:

$required_fields = array('name', 'phone', 'email', 'mobile', 'state', 'street', 'city');

The 'check-for-existence' code can then be simplified to:

foreach ($required_fields as $f) {
    if (!isset($_POST[$f])) {
        // something is up
    }
}

The better way ™

However, you should seriously consider combining both existence and validation / sanitization checks. PHP provides a family of filter functions functions that you can use to validate and/or sanitize your input variables. For example, to get equivalent behavior as above:

$required_fields = filter_input_array(INPUT_POST, array(
    'name' => FILTER_UNSAFE_RAW,
    'email' => FILTER_VALIDATE_EMAIL,
));

if (is_null($required_fields) || in_array(null, $required_fields, true)) {
    // some fields are missing
}

Fields that exist but fail validation will be set to false, so this is how you detect such an event:

foreach ($required_fields as $name => $value) {
    if (false === $value) {
        // field $name failed validation (e.g. bad email format)
    } elseif (!strlen(trim($value))) {
        // field is empty
    }
}

The best way would be to create some sort of form validator. However you can use this function:

<?php
    function isAnyEmpty() {
        $total = 0;
        $args = func_get_args();
        foreach($args as $arg)
        {
            if(empty($arg)) {
                return true;
            }
        }

        return false;
    }
    $var1 = 1;
    $var2 = 'test';
    $var3 = '';

    if(isAnyEmpty($var1, $var2, $var3)) {
        echo 'empty fields!';
    }
?>

You could try creating a general validation class that could be reused and be more precise.

Some pseudo code:

<?

class validateFields {
    $validators = array(
        "name" => array(
            "empty" => array(
                "rule"          => "some regex",
                "errorMessage"  => "name may not be empty"
            ),
            "noNumbers" => array(
                "rule"          => "some regex",
                "errorMessage"  => "No numbers are allowed in the name field"
            )
        ),
        "otherVariable" => array(
            "atLeast50chars" => array(
                "rule"          => "some regex",
                "errorMessage"  => "This field must be at least 50 chars"
            )
        )
    );


    public function Validate($post){
        $errors = array();

        foreach($_POST as $key => $value){
            if(!array_key_exists($key, $validators)) {
                continue;
            }

            foreach($validators[$key] as $validator) {
                if(!preg_match($validator["rule"], $value) {
                    $errors[$key] = $validator["errorMessage"];
                    break;
                }
            }
        }

        return $errors;
    }
}


?>

Then in your code you could do something like:

$errors = Validate($_POST);
foreach($error as $errorMessage) {
    echo $errorMessage . "</br>";
}

Of course you could fancy this up, adding divs with classes right below/beside the concerning input field and load the $errorMessage into there. I'm sure there's loads of examples out there :)

You can write Foreach loop

  foreach($_POST as $key => $value) 
    {
        if (!isset($_POST[$key]) || empty($_POST[$key])
        {
            echo '<div class="something">You have empty fields!!!</div>';
        }
    }