如何写入与HTML表单字段同名的文件

I have made an attempt to write a PHP code that takes the contents of an HTML form then write them into a file. I have that down just fine, but I have another problem. I want to take an input of a field in the form and make it the file name that I am writing to.

Here is my PHP code:

<?php
if(isset($_POST['forwhom']) && isset($_POST['importance']) && isset($_POST['message'])) {
$file = "students.html";
$data = nl2br('-' . $_POST['forwhom'] . ':' . ' ' . $_POST['message']  . ' ' . $_POST['importance'] . "
");
$ret = file_put_contents($file, $data, FILE_APPEND | LOCK_EX);
if($ret === false) {
    die('There was an error writing this file');
}
else {
    echo "Success!  Student added to database.";
}
}
else {
   die('no post data to process');
}

?>

Currently, I am writing to the file "students.html" However, I want to write to the file "Dad.html", which happens to be the input in the field by the name of forwhom.

Basically, I am asking this: What do I use to replace "students.html" (line 3) so that the file name will be the same as the input of the field forwhom?

I apologize if that didn't make any sense. Thank you very much!

  1. First check if data has been posted on your form using $_SERVER['REQUEST_METHOD'] == "POST".

  2. For simplicity sake save all your "POST" requests in a variable eg.

    $file = $_POST['forwhom'];
    $importance = $_POST['importance'];
    $message = $_POST['message'];

  3. I sometimes find it much easier using empty() instead of isset().

  4. Create a variable, lets say $status which would store all your messages, then any where in your HTML section you just use the $status to display the appropriate message to the user. Check below how i make use of $status in the form. By doing so is much cleaner and makes your code more dynamic in a sense.

             <?php

            if ($_SERVER['REQUEST_METHOD'] == "POST") {

                $file = $_POST['forwhom'];  
                $importance = $_POST['importance'];
                $message = $_POST['message'];

                if (!empty($file) && !empty($importance) && !empty($message)) {

                    $data = nl2br('-' . $file . ':' . ' ' . $message  . ' ' . $importance . "
");      
                    $file .= ".html";       
                    $ret = file_put_contents($file, $data, FILE_APPEND | LOCK_EX);

                    if ($ret == true) {
                        $status = "Success!  Student added to database.";
                    } else {
                        $status = "Error writing to file!";
                    }
                } else {
                    $status = "Please enter name, email and message";
                }

            }
            ?>
    <!DOCTYPE html>
    <html>
    <head>
        <title></title>
    </head>
    <body>
    <form action="" method="post">
        <ul>
            <li>
                <label for="name">Name: </label>
                <input type="text" name="forwhom" id="forwhom">
            </li>
            <li>
                <label for="email">Email: </label> 
                <input type="text" name="importance" id="importance"> 
            </li>
            <li>
                <label for="message">Your Message: </label><br>
                <textarea name="message" id="message"></textarea>
            </li>
            <li>
                <input type="submit" value="Go!">
            </li>
        </ul>
    <?php if(isset($status)): ?>
    <p><?= $status; ?></p>
    <?php endif; ?>
    </form>
    </body>
    </html>

    I added a form just for explanation sake, hope it helps.