Verify that all $ _POST was sent without using many ifs

Good morning,

I have to check if all fields of the form, sent as $ _POST, have not been blank, this is until I solved it. But I wanted to see a way to not need to use many if / elif to check every index of $ _POST would:

if(empty($_POST['nome'])){?>
    <p>Campo NOME em branco</p>
<?php}
elif(empty($_POST['cpf'])){?>
    <p>Campo CPF em branco</p>
<?php}
elif(empty($_POST['endereco'])){?>
    <p>Campo ENDERECO em branco</p>
<?php}
...
else{

$nome = $_POST['nome'];
$cpf = $_POST['cpf'];
$endereco = $_POST['endereco'];
?>

I just tried to use if (empty ($ _ POST)) but it did not work, I let it go even with the blank fields.

You can greatly simplify logic if you use an auxiliary array for the fields you are interested in. In this case you can iterate the fields with a foreach and test if each is set to $_POST , and display its blank field text when it is not.

Example:

$valido = true;
$campos = Array("nome", "cpf", "endereco");

foreach ($campos as $campo){
    if (empty($_POST[$campo])){
        echo "<p>Campo $campo em branco</p>";
        $valido = false;
    }
}

if ($valido){
    $nome = $_POST['nome'];
    $cpf = $_POST['cpf'];
    $endereco = $_POST['endereco']; 
    //resto do código
}

In this way even if you have more fields to check if they are filled, you just need to add them in the $campos array.

Try to check if the value is empty, even if it is not filled it will return null and null is already considered a value, it also verifies if it exists, by placing the! isset.
It would look like this: if ( !isset( $_POST ) || empty( $_POST ) )

You can do this with a foreach , it would look something like this:

foreach ($_POST as $key => $value){
    if (empty($value)){
        echo "<p>Campo ".$key." em branco</p>";
        exit;
    }
}

$nome = $_POST['nome'];
$cpf = $_POST['cpf'];
$endereco = $_POST['endereco'];

If a blank field is found within the $_POST variable, it displays a message and ends the program.

From php5.5 empty() started evaluating expressions, not just variables. One way to solve the problem is to connect all fields through conjunctions (common E logical) and let if take care of the expression result.

Important: If any of the values contains zero it will be evaluated as false which will generate a false positive,

$_POST = array('id' => '', 'nome' => 'fulano', 'email' => 'fulano@email.com');

if(!empty($_POST['id'] && $_POST['nome'] && $_POST['email'])){
    echo 'campos válidos';
}else{
    echo 'campos inválidos';
}

echo "<pre>";
print_r($_POST);

Example – ideone

I work as follows in my projects:

1 – I leave input obligatorily, putting required :

<input type="text" name="nome" placeholder="Nome" required>

Thus, the form is not sent without this filled field.

2 – In my PHP file that receives the value, I do it as follows:

$nome = $_POST['nome'] ? $_POST['nome'] : NULL;

I use a ternary conditional. If my PHP file is receiving the name field, assigns the value to the variable, if it does not, assign NULL .
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You can also use isset of PHP. That checks whether the variable was started:

$nome = isset($_POST['nome']) ? $_POST['nome'] : NULL;