Invalid argument supplied for foreach()

Question

Hi, I've got a code that echos out every row of the database with a checkbox next to it.

$result = mysqli_query($database, "SELECT * FROM $imei_to_look_for" );
while ( $row = mysqli_fetch_array($result) ) {

echo htmlspecialchars($imei_to_look_for).
"<input type='checkbox' value='$row[event_number]' name='todelete[]' />";

and another, that should loop throught all checked checkboxes.

foreach ( $_POST['todelete'] as $delete_id ) { ...

yet it gives an "Invalid argument supplied for foreach()" error.

Any suggestions? Thanks!

Answer 1

That error is typically caused by passing something other than an array (or other iterable object) into foreach.

Have you done a var_dump or print_r on $_POST to ensure that todelete[] is actually coming through as an array?

Answer 2

Replace

foreach ( $_POST['todelete'] as $delete_id ) { ...

with

if( is_array( $_POST['todelete'] ) ) {
    foreach ( $_POST['todelete'] as $delete_id ) { ...
} else {
    echo "$_POST['todelete'] is not an array";
}

This will prevent your code erroring when you haven't received an array, and help you debug the POST data (which is apparently not what you're expecting).

Answer 3

Have you tried moving the name='todelete[]' to the select tag? It seems you have it declared in the wrong place in your select/options html.

An example here: http://www.onlinetools.org/tricks/using_multiple_select.php

Answer 4

GOT IT! I just forgot that line on top! :)))

  <form id="form1" name="form1" method="post" action="">