How to Prevent Unintentional Data Insertion on Page Refresh?

Avoiding Unintentional Data Insertion on Page Refresh

In web application development, it is crucial to prevent unintended data insertion when users refresh a page after submitting a form. One common approach to this issue is to redirect users to a different page after form submission.

Consider the following code snippet where a form is used to insert data into a database:

<?php
    if (isset($_POST['name'])) {
        // Operation on database, such as inserting $_POST['name'] into a table
        echo "Operation Done";
        die(); // Die() is used to prevent further processing, which would otherwise cause the form to be resubmitted on page refresh.
    }
?>

<form action='page.php' method='post' name="myForm">
    <input type="text" maxlength="50" name="name" class="input400" />
    <input type="submit" name="Submit" />
</form>

When the form is submitted, the data is inserted into the database, and the "Operation Done" message is displayed. However, if a user refreshes the page, the form will be resubmitted, causing the data to be inserted again.

To avoid this issue, it is recommended to redirect the user to a different page after the form submission. This prevents the form from being resubmitted on page refresh:

<?php
    if (isset($_POST['name'])) {
        // Operation on database, such as inserting $_POST['name'] into a table
        // Set a success flash message (assuming you are using a framework).
        header('Location: /path/to/record'); // Redirects the user to a different page upon successful form submission.
        exit; // Die() is not necessary here since the header redirect will send the user away from the page.
    }
?>

<form action='page.php' method='post' name="myForm">
    <input type="text" maxlength="50" name="name" class="input400" />
    <input type="submit" name="Submit" />
</form>

By redirecting the user to a different page after form submission, the risk of unintended data insertion on page refresh is eliminated.

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