Question

This starts when a user fills out a form with optional inputs. The values are passed by AJAX to another PHP page to insert into a database. If a particular input is empty, I don’t want to update the data stored in the database. Is there a way to check, besides writing lots of if statements, to see if an input value is empty? If it is empty, how can I write the statement so MySQL won’t update the corresponding field in the database?

if(isset($_POST['f_name']) && isset($_POST['m_name']) && isset($_POST['l_name']) && isset($_POST['alt_name'])){
    $fname = $_POST['f_name'];
    $mname = $_POST['m_name'];
    $lname = $_POST['l_name'];
    $altname = $_POST['alt_name'];

If some of the $_POST entries are empty, then they shouldn’t be put into the database. I’m saying this because if there’s already an existing value in the database, I don’t want to overwrite the value with an empty one.

Answer 1

In this case you also don’t allow people to enter just a blank space / &bnsp;

<?php
$empty = FALSE;

foreach ($_POST as $key)
{
    if (!isset($key) || strlen(trim($key)) != 0)
    {
      $empty = TRUE;
    }
}

if (!$empty)
{
    $fname = $_POST['f_name'];
    $mname = $_POST['m_name'];
    $lname = $_POST['l_name'];
    $altname = $_POST['alt_name'];
}
?>