1 – Add Payment Type to WooCommerce Admin Email

add_action( 'woocommerce_email_after_order_table', 'add_payment_method_to_admin_new_order', 15, 2 );
 
function add_payment_method_to_admin_new_order( $order, $is_admin_email ) {
  if ( $is_admin_email ) {
    echo '<p><strong>Payment Method:</strong> ' . $order->payment_method_title . '</p>';
  }
}

2 – Up-sells products per page / per line

remove_action( 'woocommerce_after_single_product_summary', 'woocommerce_upsell_display', 15 );
add_action( 'woocommerce_after_single_product_summary', 'woocommerce_output_upsells', 15 );
 
if ( ! function_exists( 'woocommerce_output_upsells' ) ) {
	function woocommerce_output_upsells() {
	    woocommerce_upsell_display( 3,3 ); // Display 3 products in rows of 3
	}
}

3 – Remove product categories from shop page

add_action( 'pre_get_posts', 'custom_pre_get_posts_query' );

function custom_pre_get_posts_query( $q ) {
 
	if ( ! $q->is_main_query() ) return;
	if ( ! $q->is_post_type_archive() ) return;
	
	if ( ! is_admin() && is_shop() && ! is_user_logged_in() ) {
 
		$q->set( 'tax_query', array(array(
			'taxonomy' => 'product_cat',
			'field' => 'slug',
			'terms' => array( 'color', 'flavor', 'spices', 'vanilla' ), // Don't display products in these categories on the shop page
			'operator' => 'NOT IN'
		)));
	
	}
 
	remove_action( 'pre_get_posts', 'custom_pre_get_posts_query' );
 
}

4 – Quickly translate any string

add_filter('gettext',  'translate_text');
add_filter('ngettext',  'translate_text');
 
function translate_text($translated) {
     $translated = str_ireplace('Choose and option',  'Select',  $translated);
     return $translated;
}

5 – Exclude a category from the WooCommerce category widget

add_filter( 'woocommerce_product_categories_widget_args', 'woo_product_cat_widget_args' );

function woo_product_cat_widget_args( $cat_args ) {
	
	$cat_args['exclude'] = array('16');
	
	return $cat_args;
}

6 – Add a custom field to a product variation

//Display Fields
add_action( 'woocommerce_product_after_variable_attributes', 'variable_fields', 10, 2 );
//JS to add fields for new variations
add_action( 'woocommerce_product_after_variable_attributes_js', 'variable_fields_js' );
//Save variation fields
add_action( 'woocommerce_process_product_meta_variable', 'variable_fields_process', 10, 1 );

function variable_fields( $loop, $variation_data ) { ?>	
	<tr>
		<td>
			<div>
					<label></label>
					<input type="text" size="5" name="my_custom_field[]" value=""/>
			</div>
		</td>
	</tr>

<tr>
		<td>
			<div>
					<label></label>
					
			</div>
		</td>
	</tr>
<?php }
 
function variable_fields_process( $post_id ) {
	if (isset( $_POST['variable_sku'] ) ) :
		$variable_sku = $_POST['variable_sku'];
		$variable_post_id = $_POST['variable_post_id'];
		$variable_custom_field = $_POST['my_custom_field'];
		for ( $i = 0; $i < sizeof( $variable_sku ); $i++ ) :
			$variation_id = (int) $variable_post_id[$i];
			if ( isset( $variable_custom_field[$i] ) ) {
				update_post_meta( $variation_id, '_my_custom_field', stripslashes( $variable_custom_field[$i] ) );
			}
		endfor;
	endif;
}

7 – Replace “Out of stock” by “sold”

add_filter('woocommerce_get_availability', 'availability_filter_func');

function availability_filter_func($availability)
{
	$availability['availability'] = str_ireplace('Out of stock', 'Sold', $availability['availability']);
	return $availability;
}

8 – Display “product already in cart” instead of “add to cart” button

/**
 * Change the add to cart text on single product pages
 */
add_filter( 'woocommerce_product_single_add_to_cart_text', 'woo_custom_cart_button_text' );

function woo_custom_cart_button_text() {

	global $woocommerce;
	
	foreach($woocommerce->cart->get_cart() as $cart_item_key => $values ) {
		$_product = $values['data'];
	
		if( get_the_ID() == $_product->id ) {
			return __('Already in cart - Add Again?', 'woocommerce');
		}
	}
	
	return __('Add to cart', 'woocommerce');
}

/**
 * Change the add to cart text on product archives
 */
add_filter( 'add_to_cart_text', 'woo_archive_custom_cart_button_text' );

function woo_archive_custom_cart_button_text() {

	global $woocommerce;
	
	foreach($woocommerce->cart->get_cart() as $cart_item_key => $values ) {
		$_product = $values['data'];
	
		if( get_the_ID() == $_product->id ) {
			return __('Already in cart', 'woocommerce');
		}
	}
	
	return __('Add to cart', 'woocommerce');
}

9 – Hide products count in category view

add_filter( 'woocommerce_subcategory_count_html', 'woo_remove_category_products_count' );

function woo_remove_category_products_count() {
	return;
}

10 – Make account checkout fields required

add_filter( 'woocommerce_checkout_fields', 'woo_filter_account_checkout_fields' );
 
function woo_filter_account_checkout_fields( $fields ) {
	$fields['account']['account_username']['required'] = true;
	$fields['account']['account_password']['required'] = true;
	$fields['account']['account_password-2']['required'] = true;

	return $fields;
}

11 – Rename a product tab

add_filter( 'woocommerce_product_tabs', 'woo_rename_tab', 98);
function woo_rename_tab($tabs) {

 $tabs['description']['title'] = 'More info';

 return $tabs;
}

12 – List WooCommerce product Categories

$args = array(
    'number'     => $number,
    'orderby'    => $orderby,
    'order'      => $order,
    'hide_empty' => $hide_empty,
    'include'    => $ids
);

$product_categories = get_terms( 'product_cat', $args );

$count = count($product_categories);
 if ( $count > 0 ){
     echo "<ul>";
     foreach ( $product_categories as $product_category ) {
       echo '<li><a href="' . get_term_link( $product_category ) . '">' . $product_category->name . '</li>';
        
     }
     echo "</ul>";
 }

13 – Replace shop page title

add_filter( 'woocommerce_page_title', 'woo_shop_page_title');

function woo_shop_page_title( $page_title ) {
	
	if( 'Shop' == $page_title) {
		return "My new title";
	}
}

14 – Change a widget title

/*
 * Change widget title
 */
add_filter( 'widget_title', 'woo_widget_title', 10, 3);

function woo_widget_title( $title, $instance, $id_base ) {
	
	if( 'onsale' == $id_base) {
		return "My new title";
	}
}

15 – Remove WooCommerce default settings

add_filter( 'woocommerce_catalog_settings', 'woo_remove_catalog_options' );

function woo_remove_catalog_options( $catalog ) {

	unset($catalog[23]); //Trim zeros (no) 
	unset($catalog[22]); //2 decimals 
	unset($catalog[21]); //decimal sep (.) 
	unset($catalog[20]); //thousand sep (,) 
	unset($catalog[19]); //currency position (left)	
	unset($catalog[18]); //currency position (left)	
	unset($catalog[5]); // ajax add to cart (no)	
	
	return $catalog; 
}

16 – Change “from” email address

function woo_custom_wp_mail_from() {
        global $woocommerce;
        return html_entity_decode( 'your@email.com' );
}
add_filter( 'wp_mail_from', 'woo_custom_wp_mail_from', 99 );

17 – Decode from name in WooCommerce email

function woo_custom_wp_mail_from_name() {
        global $woocommerce;
        return html_entity_decode( get_option( 'woocommerce_email_from_name' ) );
}
add_filter( 'wp_mail_from_name', 'woo_custom_wp_mail_from_name', 99 );

function woo_custom_wp_mail_from() {
        global $woocommerce;
        return html_entity_decode( get_option( 'woocommerce_email_from' ) );
}
add_filter( 'wp_mail_from_name', 'woo_custom_wp_mail_from_name', 99 );

18 – Return featured products ids

function woo_get_featured_product_ids() {
	// Load from cache
	$featured_product_ids = get_transient( 'wc_featured_products' );

	// Valid cache found
	if ( false !== $featured_product_ids )
		return $featured_product_ids;

	$featured = get_posts( array(
		'post_type'      => array( 'product', 'product_variation' ),
		'posts_per_page' => -1,
		'post_status'    => 'publish',
		'meta_query'     => array(
			array(
				'key' 		=> '_visibility',
				'value' 	=> array('catalog', 'visible'),
				'compare' 	=> 'IN'
			),
			array(
				'key' 	=> '_featured',
				'value' => 'yes'
			)
		),
		'fields' => 'id=>parent'
	) );

	$product_ids = array_keys( $featured );
	$parent_ids  = array_values( $featured );
	$featured_product_ids = array_unique( array_merge( $product_ids, $parent_ids ) );

	set_transient( 'wc_featured_products', $featured_product_ids );

	return $featured_product_ids;
}

19 – Add custom field to edit address page

// add fields to edit address page
function woo_add_edit_address_fields( $fields ) {

	$new_fields = array(
				'date_of_birth'     => array(
				'label'             => __( 'Date of birth', 'woocommerce' ),
				'required'          => false,
				'class'             => array( 'form-row' ),
			),
		);
		
	$fields = array_merge( $fields, $new_fields );
	
    return $fields;
	
}

add_filter( 'woocommerce_default_address_fields', 'woo_add_edit_address_fields' );

20 – Display onsale products catalog shortcode

function woocommerce_sale_products( $atts ) {

    global $woocommerce_loop;

    extract(shortcode_atts(array(
        'per_page'  => '12',
        'columns'   => '4',
        'orderby' => 'date',
        'order' => 'desc'
    ), $atts));

    $woocommerce_loop['columns'] = $columns;

    $args = array(
        'post_type' => 'product',
        'post_status' => 'publish',
        'ignore_sticky_posts'   => 1,
        'posts_per_page' => $per_page,
        'orderby' => $orderby,
        'order' => $order,
        'meta_query' => array(
            array(
                'key' => '_visibility',
                'value' => array('catalog', 'visible'),
                'compare' => 'IN'
            ),
            array(
                'key' => '_sale_price',
                'value' =>  0,
                'compare'   => '>',
                'type'      => 'NUMERIC'
            )
        )
    );
    query_posts($args);
    ob_start();
    woocommerce_get_template_part( 'loop', 'shop' );
    wp_reset_query();

    return ob_get_clean();
}

add_shortcode('sale_products', 'woocommerce_sale_products');

21 – Have onsale products

function woo_have_onsale_products() {
	
	global $woocommerce;

	// Get products on sale
	$product_ids_on_sale = array_filter( woocommerce_get_product_ids_on_sale() );

	if( !empty( $product_ids_on_sale ) ) {
		return true;
	} else {
		return false;
	}
	
}

// Example:
if( woo_have_onsale_products() ) {
	echo 'have onsale products';
} else {
	echo 'no onsale product';
}

22 – Set minimum order amount

add_action( 'woocommerce_checkout_process', 'wc_minimum_order_amount' );
function wc_minimum_order_amount() {
	global $woocommerce;
	$minimum = 50;
	if ( $woocommerce->cart->get_cart_total(); < $minimum ) {
           $woocommerce->add_error( sprintf( 'You must have an order with a minimum of %s to place your order.' , $minimum ) );
	}
}

23 – Order by price, date or title on shop page

add_filter('woocommerce_default_catalog_orderby', 'custom_default_catalog_orderby');
 
function custom_default_catalog_orderby() {
     return 'date'; // Can also use title and price
}

24 – Redirect add to cart button to checkout page

add_filter ('add_to_cart_redirect', 'redirect_to_checkout');

function redirect_to_checkout() {
    global $woocommerce;
    $checkout_url = $woocommerce->cart->get_checkout_url();
    return $checkout_url;
}

25 – Add email recipient when order completed

function woo_extra_email_recipient($recipient, $object) {
    $recipient = $recipient . ', your@email.com';
    return $recipient;
}
add_filter( 'woocommerce_email_recipient_customer_completed_order', 'woo_extra_email_recipient', 10, 2);

And… that’s it! I hope you find will these snippets useful, they were all tested and they all work fine, but if you experience any trouble please let me know  the comments section. Have fun! 😉