Php Trying to get property 'ID' of non-object

Question

I am using this code in a page template to determine the custom post type and display a different template for each custom post type.

if ( $query->have_posts() )
 {
    ?>
 <ul id="floros">
    <?php
    while ($query->have_posts())
    {
        $query->the_post();

        ?>

<?php
    $curtype = get_post_type( $post->ID );
    switch ($curtype) {
        case "events":
        ?>

        <?php
        break;
        case "brands":
        ?>
..etc

However i have an issue with this line: $curtype = get_post_type( $post->ID );

Trying to get property 'ID' of non-object in search-filter/results.php on line 37
PHP Notice:  Undefined variable: post in search-filter/results.php on line 37

The page shows results as expected, however the debug log is filled with duplicated lines of the above. I suppose I need to somehow check only for the type of the first object to avoid this error?

Answer 1

The error says it all. You are trying to get property ID of non-object. That means that the $post var is not an object.

You can get current post ID within a WordPress loop using get_the_ID(), but actually you don't need it in this case (see explanation below).

if ( $query->have_posts() ) {

    while ( $query->have_posts() ) {

        $query->the_post();

        $current_post_type = get_post_type( get_the_ID() );

        // Use $query->post if you want to get
        // current post object in full
        // ex: $query->post->ID

    }

    // Do not forget to reset post data after a custom wp_query loop
    // to restore global $post to main wp_query data
    wp_reset_postdata();

}

PD: Actually, $query->the_post() sets global $post to current post within the loop, and get_post_type() checks global $post if it doesn't receive a different post data or ID, that is why your code works as expected despite the error.