Form Submission and File Upload in PHP - Basic to Advance Level Form Submission in PHP
Categories - PHP Tags - PHP   Maniruzzaman Akash   2 weeks ago   53   0

Form Submission and File Upload in PHP - Basic to Advance Level Form Submission in PHP

Form submission in PHP is a very important thing. In every phase, when we’ll work with database, we must use a form and make some save/checking with database. So form is a very important thing for Web Development. Today we’ll learn a complete form submission using PHP.

Basic Form Submission

Let’s make a basic form submission in PHP -

<h2>Contact Us</h2>

<?php
// We'll handle our form submission logic here. Let's just make Form Submitted. text if form is submitted.
if (isset($_POST['contact_form'])) {
    echo "Form Submitted.";
}
?>
<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">

    <label for="name">Name</label><br>
    <input type="text" id="name" name="name"> <br>
    <br>

    <label for="email">Email</label><br>
    <input type="email" id="email" name="email"> <br>
    <span style="color: red"><?php echo !empty($errors['email']) ? $errors['email'] : '' ?></span>
    <br>

    <label for="subject">Subject</label><br>
    <input type="text" id="subject" name="subject"> <br>
    <span style="color: red"><?php echo !empty($errors['subject']) ? $errors['subject'] : '' ?></span>
    <br>

    <input type="submit" value="Send" name="contact_form" />
</form>

Look in php first line -

if (isset($_POST['contact_form'])) {
    echo "Form Submitted.";
}

isset($_POST['contact_form']) == true if someone submit the form.

here, we’re first checking if someone click on submit button of contact_form. For this, one must have to provide a name="contact_form" value in input. like so -

<input type="submit" value="Send" name="contact_form" />

And, we’ld make our method="post" as we’ll handle everything in POST request. We can also do that in GET request. But POST request is more secured than GET request. Like so in form -

<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">

Input Validation in PHP

Let’s now make a simple form validation in PHP by just checking if an input is empty or not -

<h2>Contact Us</h2>

<?php
if (isset($_POST['contact_form'])) {
    if (empty($_POST['name'])) {
        echo 'Please give a valid name.<br>';
    }

    if (empty($_POST['email'])) {
        echo 'Please give an email address.<br>';
    }

    if (empty($_POST['subject'])) {
        echo 'Please give a subject.<br>';
    }
}
?>
<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">

    <label for="name">Name</label><br>
    <input type="text" id="name" name="name"> <br>
    <br>

    <label for="email">Email</label><br>
    <input type="email" id="email" name="email"> <br>
    <br>

    <label for="subject">Subject</label><br>
    <input type="text" id="subject" name="subject"> <br>
    <br>

    <input type="submit" value="Send" name="contact_form" />
</form>

So, Output would be like this after empty form submission -

Output:

Input Validation in PHP

Form Submission with Global Errors variable Managed

Let’s now store our errors in $errors[] and then process from this -

<h2>Contact Us</h2>

<?php
$errors = [];

if (isset($_POST['contact_form'])) {
    if (empty($_POST['name'])) {
        $errors['name'] = "Please give a valid name.";
    }

    if (empty($_POST['email'])) {
        $errors['email'] = "Please give an email address.";
    }

    if (empty($_POST['subject'])) {
        $errors['subject'] = "Please give a subject.";
    }
}
?>

<?php if (count($errors)) : ?>
    <div style='border: 1px solid red; padding: 10px; margin: 10px;'>
        <?php foreach ($errors as $error) : ?>
            <p style="color: red;"><?php echo $error; ?></p>
        <?php endforeach; ?>
    </div>
<?php endif; ?>

<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">
    <label for="name">Name</label><br>
    <input type="text" id="name" name="name"> <br>
    <br>

    <label for="email">Email</label><br>
    <input type="email" id="email" name="email"> <br>
    <br>

    <label for="subject">Subject</label><br>
    <input type="text" id="subject" name="subject"> <br>
    <br>

    <input type="submit" value="Send" name="contact_form" />
</form>

So, it’s now little improved, right. After getting any error, we’re adding that with an index in $errors variable.

if (empty($_POST['name'])) {
     $errors['name'] = "Please give a valid name.";
}

Then show all of the errors one by one using a foreach loop -

<?php if (count($errors)) : ?>
    <div style='border: 1px solid red; padding: 10px; margin: 10px;'>
        <?php foreach ($errors as $error) : ?>
            <p style="color: red;"><?php echo $error; ?></p>
        <?php endforeach; ?>
    </div>
<?php endif; ?>

File Upload in PHP -

move_uploaded_file() is used to upload any file in php - https://www.php.net/manual/en/function.move-uploaded-file.php

 move_uploaded_file(string $from, string $to): bool

** So, this function takes **

  1. a file name as first parameter and
  2. File location to store in second parameter.

**Returns - ** Boolean(true) if file is uploaded successfully.

Simple File Upload Example -

Create a uploads folder in root, so that uploaded image could be moved in this folder.

<?php
if (isset($_POST['contact_form'])) {

    // Upload file if any file is provided
    if (!empty($_FILES['attachment']['name'])) {
        if (move_uploaded_file($_FILES['attachment']['tmp_name'], "uploads/" . $_FILES['attachment']['name'])) {
            echo "File Uploaded.";
        } else {
            echo "File Upload Failed.";
        }
    }
}
?>

<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>" enctype="multipart/form-data">

    <label for="attachment">Attachment (PDF or Image) (optional)</label><br>
    <input type="file" id="attachment" name="attachment"> <br>
    <span style="color: red"><?php echo !empty($errors['attachment']) ? $errors['attachment'] : '' ?></span>
    <br>

    <input type="submit" value="Send" name="contact_form" />
</form>

Great, after clicking send you’ll check a file has been uploaded. Forgettable Requirements in File Upload

  1. In form, there would be enctype property value set to enctype="multipart/form-data". Without this, no image would be uploaded.
  2. move_uploaded_file($_FILES['attachment']['tmp_name'], "uploads/" . $_FILES['attachment']['name'])
  3. We must need to check if file is given like so - if (!empty($_FILES['attachment']['name'])) {

Final Form Submission with Validation, Security, File Upload -

<h2>Contact Us</h2>

<?php
$errors = [];

try {
    if (isset($_POST['contact_form'])) {

        // Validation
        if (empty($_POST['name'])) {
            $errors['name'] = "Please give a valid name.";
            // throw new Exception("Please give a valid name.", 1);
        }

        if (empty($_POST['email'])) {
            $errors['email'] = "Please give an email address.";
        }

        if(!filter_var($_POST['email'], FILTER_VALIDATE_EMAIL)) {
            $errors['email'] = "Please give a valid email.";
        }

        if (empty($_POST['subject'])) {
            $errors['subject'] = "Please give a valid subject.";
        }

        if (empty($_POST['temp_password'])) {
            $errors['temp_password'] = "Please give a valid temporary password.";
        }

        // Upload file
        $file_name = null;
        if (!empty($_FILES['attachment']['name'])) {

            // Undefined | Multiple Files | $_FILES Corruption Attack
            // If this request falls under any of them, treat it invalid.
            if (
                !isset($_FILES['attachment']['error']) ||
                is_array($_FILES['attachment']['error'])
            ) {
                throw new RuntimeException('Invalid parameters.');
            }

            // Check file size exceeded or not
            $file_size = !empty($_FILES['attachment']['size']) ? intval($_FILES['attachment']['size']) : 0;
            $upto_supported_size = 5 * 1024 * 1000; // 5MB

            if ($file_size > $upto_supported_size) {
                $errors['attachment'] = "File size exceeded. Max upload limit is 5MB";
                throw new Exception($errors['attachment'], 1);
            }

            // Mime type of file
            $finfo = new finfo(FILEINFO_MIME_TYPE);
            $file_ext = array_search(
                $finfo->file($_FILES['attachment']['tmp_name']),
                array(
                    'jpg' => 'image/jpg',
                    'jpg' => 'image/jpeg',
                    'png' => 'image/png',
                    'gif' => 'image/gif',
                    'gif' => 'image/bnf',
                    'pdf' => 'application/pdf'
                ),
                true
            );

            if (false === $file_ext) {
                $errors['attachment'] = "File should be a valid image or PDF file";
                throw new Exception($errors['attachment'], 1);
            }

            // Sanitize file name and make a new name
            $file_name = 'devsenv-' . time() . '.' . $file_ext;

            // Upload file
            if (!move_uploaded_file($_FILES['attachment']['tmp_name'], "uploads/" . $file_name)) {
                $errors['attachment'] = "File uploads fail, please try again.";
                throw new Exception($errors['attachment']);
            }
        }
    }
} catch (\Exception $e) {
    $errors['global'] = $e->getMessage();
}

if (count($errors) > 0) {
    $err_global = "Failed to submit form. Please try again.";

    if (isset($errors['global'])) {
        $err_global .= ' Error: ' .$errors['global'];
    }

    $errors['global'] = $err_global;
} else {
    if (isset($_POST['contact_form'])) {
        // Sanitization
        $insert_data = [
            'name'          => htmlspecialchars($_POST['name']),
            'email'         => filter_var($_POST['email'], FILTER_VALIDATE_EMAIL),
            'subject'       => htmlspecialchars($_POST['subject']),
            'temp_password' => htmlspecialchars($_POST['temp_password']),
            'attachment'    => $file_name
        ];
        var_dump($insert_data);

        // Insert into Database
        // DB::insert('contact_us', $insert_data);
    }
}

?>

<?php
if (!empty($errors['global'])) {
    echo "<p style='color:red; border: 1px solid #ccc; padding: 10px;'>" . $errors['global'] . "</p>";
} elseif (isset($_POST['contact_form'])) {
    echo "<p style='color:green'>Your form is submitted !</p>";
}
?>
<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>" enctype="multipart/form-data">

    <label for="name">Name</label><br>
    <input type="text" id="name" name="name"> <br>
    <span style="color: red"><?php echo !empty($errors['name']) ? $errors['name'] : '' ?></span>
    <br>

    <label for="email">Email</label><br>
    <input type="email" id="email" name="email"> <br>
    <span style="color: red"><?php echo !empty($errors['email']) ? $errors['email'] : '' ?></span>
    <br>

    <label for="subject">Subject</label><br>
    <input type="text" id="subject" name="subject"> <br>
    <span style="color: red"><?php echo !empty($errors['subject']) ? $errors['subject'] : '' ?></span>
    <br>

    <label for="temp_password">Temp Password</label><br>
    <input type="password" id="temp_password" name="temp_password"> <br>
    <span style="color: red"><?php echo !empty($errors['temp_password']) ? $errors['temp_password'] : '' ?></span>
    <br>

    <label for="attachment">Attachment (PDF or Image) (optional)</label><br>
    <input type="file" id="attachment" name="attachment"> <br>
    <span style="color: red"><?php echo !empty($errors['attachment']) ? $errors['attachment'] : '' ?></span>
    <br>

    <input type="submit" value="Send" name="contact_form" />
</form>
Final form submission in PHP

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