警告：为foreach（）和PHP提供的参数无效警告：array_diff（）：参数＃1不是数组

Question

The objective is that matched ids are removed, returning the remaining values in an array.

This is my script:

function example($link, $onlist)
{
    //$newarray = array();
    $newarray = implode(',', $onlist);
    foreach ($newarray as $key)
    {
        $query = mysql_query("select * from table where id = '".$newarray."'");
        $existing = array();
        while($cz = mysql_fetch_assoc($query))
        {
            $existing[] = $cz['id'];
        }
    }

    $ex = array_diff($newarray, $existing);
    return $ex;
}

If I run this script. It shows errors:

PHP Warning: array_diff(): Argument #1 is not an array Warning: Invalid argument supplied for foreach() .

Please share suggestions with me.

Answer 1

This error occurs because after running implode on the $newarray it is converted into string that's why it's giving you that error. For more info check php manual

http://us3.php.net/implode

implode returns string