How to display a WordPress Custom Field only on a specific day of the week?

Question

I've got WordPress site for which I've set up a custom post_type along with some custom fields created with CMB2 to display extra stuff within my custom posts.

When editing a single item for my custom post_type, it has a repeatable fields group set up in order to store prices and additional info, those are the fields:

price_tag, product_title, promo_desc, promo_price, check_promo // All fields exist within the CMB2 repeatable group, what increases the level of difficult for a new comer to php development like me...

What I need is a correct logic to output the promo_price field only if the checkbox field check_promo value = yes, if = no, then does not display/echo the promo_price field's value, then continue the logic to output the promo_price field's value only if is a specific day of the week, in this case, I thought that perhaps the WordPress Codex for Formatting Date and Time might help...

This is how I'm trying to retrieve and display them:

$foodPrices = get_post_meta( $post->ID, '_prefix_food_price_group', true ); // repeatable fields group
// A checkbox "Show promo prices?" with values no, yes exists within the metabox _prefix_food_price_group
$promoDay = date('l'); // returns Sunday

<?php       
 foreach( (array) $foodPrices as $key => $value ){
     if(!( isset( $value['price_tag'] ) ))
        continue;   

        echo '<div class="col-xs-12 col-md-4">';

        echo '<div id="price-box" class="panel">';
        echo '<div class="panel-heading text-center">';

        echo '<div id="prices-current">';

        echo ' '. $value['price_tag'] .' ';


     // if is Sunday
     if ( $promoDay == 'Sunday') {
     // display promo price if checkbox value =yes
      if( in_array( 'yes', $foodPrices ) ) {
        echo ' '. $value['promo_price'] .' ';   
      }          
     }
        echo '</div>';
        echo '<p>Serve de 1 a 2 pessoas</p>';
        echo '</div>';
        echo '<div class="panel-footer">';
     if(!( isset( $value['price_title'] ) ))
        continue;
        echo '<div id="pricetitle" class="col-xs-6 text-center">' . $value['price_title'] . '</div>';

     if(!( isset( $value['price_desc'] ) ))
        continue;
        echo '<div id="pricedesc" class="col-xs-6 text-center">' . $value['price_desc'] . '</div>';

       echo '<div class="clearfix">';
       echo '</div>';
       echo '</div>';         
       echo '</div>';
       echo '</div>';
 }
?> 

So far everything works as intended, I can successfully display the fields on my theme template. However, it seems I'm not looping correctly through the repeatable fields and/or setting the right logic in order to achieve this.

Any help is very much appreciated.

Answer 1

You are not checking the current date correctly. You need to use current_time() funciton to get current datetime according to WordPress configuration. Then, using PHP date() you can check what day of week current date is:

// Get current date time of WordPress in Unix timestamp format
$timestamp = current_time( 'timestamp' );

// Get day of the week of current date
// See http://php.net/manual/es/function.date.php
$dw = date( "w", $timestamp);

// Check day of the week: 0 for Sunday to 6 for Saturday
if( $dw == 0 ) {

    // Display content if day of the week is Sunday

}