One Array to check for form required fields- PHP

Well, it’s very easy to check if customers filled up your form with the basic HTML required Attribute.

<input type="text" required name="username">

But How do we achieve such in PHP?

Well, Here’s the logic. You have to create 2 arrays. One will hold all required field names and the Other will hold the required fields that the user submitted without a value.

<?php
    //This Array holds all required fields
    $requiredFields = ["username", "email", "phone"];

    // This Array will store required fields without a value
    $requiredFieldsMsg= [];
 ?>

Now we need to loop through the required Fields Array, to find the field without a value, and then push that field to the other array holding the required fields without a value.

<?php
    foreach($requiredFields as $requireField){
    //Check if the form field contains a value
    if(!($_POST[$requireField])) {
    /*
    if it doesn't, push the field to the
     array that will store required fields
     without a value
    */
    array_push($requiredFieldsMsg,$requireField);
    }
    }
 ?>

Now we can check if there are values in the Array holding the required fields without a value. If there are values, alert the user that the field is required, otherwise perform your (form Input Sanitization , Validation and DB insert).

<?php
    /*
    if there're values in the array holding
    the required fields, alert the user
    */
    if (isset($requiredFieldsMsg) && count($requiredFieldsMsg) > 0)
    {
    foreach($requiredFieldsMsg as $key=>$requireFieldMsg)
    {
    echo '<div align="center">
    <div class="notify">
    <p>'.$requireFieldMsg.' field is required!</p>
    </div>
    </div>'; 
    }
    }
    }
    else{
    //YOUR FORM ACTION GOES HERE
    }
?>

Here’s the full code with HTML. Just copy the codes and paste in a blank PHP file.

<?php
    //You can add as many fields as you like
    if($_POST){
    $requiredFields = [
    "username", "email",  "phone"
     ];

    /*
    Initialize the array that will store the
    fields without a value
    */
    $requiredFieldsMsg= [];

    foreach($requiredFields as $requireField){

    //Check if the form field contains a value
    if(!($_POST[$requireField])) {
    //if it doesn't, push the field to the array
      array_push($requiredFieldsMsg,$requireField);
    }
    }

    //check if there're values in the array, then alert the user
    if (isset($requiredFieldsMsg) && count($requiredFieldsMsg) > 0) {
     foreach($requiredFieldsMsg as $requireFieldMsg){
      echo '<div align="center">
      <div class="notify">
      <p>'.$requireFieldMsg.' field is required!
      </p>
      </div>
      </div>' ;
      }
    }
    }
    else
    {
     //YOUR FORM ACTION GOES HERE 
    }
    //End of script
    ?>

    <html>
    <style>
    div.notify{
    max-width:500px;
      text-align:left;
        border-radius: 4px;
        position: relative;
        padding: 1.25rem 2.5rem 1.25rem 1.5rem;
        background-color: #feecf0 !important;
        color: #cc0f35;
        margin-bottom: 10px;
    }
    </style>
    <form method="POST">
    <label>Username</label><br>
    <input type="text" name="username"><br>
    <label>Email</label><br>
    <input type="text" name="email"><br>
    <label>Phone</label><br>
    <input type="text" name="phone"><br>
    <button type="submit">TEST</button>
    </form>
 </html>

In Conclusion

You add the form fields to check in $requiredFields, passing only the name of the form field.
The script loops through the array to check if each of the form fields specified contains a value using $_POST[]
If any field does not contain a value, it will take the name of the field and add it to the other array $requiredFieldsMsg= []
Then it loops through the array $requiredFieldsMsg= [] and alerts the user that the fields are required.

UPDATE

This particular post for this PHP script has been tagged as V1.0

A well structured code for this PHP script has been published in another post and tagged V1.2

Here are the changes;

Custom field tags (eg. Email address, phone number, Social Security Number etc) are supported in V1.2 of this script.
You can store the function and use it seamlessly in all your form pages.
A return value is included. With this you can know if all fields or some fields passed the test.
You can modify the "User alert section", if you want to alert the user that some fields are missing a value.

Here's a link to V1.2 of this script

Thank You !

If you found it useful or have any other amazing feature to add, drop a comment below!

Easily Check FORM Required fields – PHP

One Array to check for form required fields

UPDATE