If you want to disable payment gateway for a specific country in WooCommerce then you have to decide the payment gateway and country code. Here I’m disabling the cod for India. You have to replace “cod” instead of your payment gateway. Have to replace “IN” instead of your decided country code. Place the following code in your functions.php file.

function disable_payment_gateway_for_a_country( $available_gateways ) {
  global $woocommerce;
  if ( isset( $available_gateways['cod'] ) && $woocommerce->customer->get_country() == 'IN' ) 
  {
    unset( $available_gateways['cod'] );
  } 
  return $available_gateways;
}
add_filter( 'woocommerce_available_payment_gateways', 'disable_payment_gateway_for_a_country' );

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If you want to remove related products from product page in WooCommerce then place the following code in your functions.php file.

function wc_remove_related_products( $args ) {
	return array();
}
add_filter('woocommerce_related_products_args','wc_remove_related_products', 10); 

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If you want to get number of items in a WooCommerce cart then you can place the following code in your file.

global $woocommerce;
$count=$woocommerce->cart->cart_contents_count;

Here $count having total number of items in your WooCommerce cart.
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You can fetch shipping address by using WC_Order object and get_shipping_address() from order id.
Use the following code to fetch shipping address from order ID.

$order = new WC_Order( $order_id );
$shipping_address=$order->get_shipping_address();

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You can fetch billing address by using WC_Order object and get_billing_address() from order id.
Use the following code to fetch billing address from order ID.

$order = new WC_Order( $order_id );
$billing_address=$order->get_billing_address();

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You can use the WC_Order object for get order date from order id.
if you have the order ID then use the following code to fetch order date.

$order = new WC_Order($order_id);
$order_date = $order->order_date;

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You can fetch all WooCommerce orders of a single customer by different parameter.
Here you can find all WooCommerce orders of a customer by user id.
Use the following to fetch all orders of a single customer in WooCommerce by user ID.
You have to replace customer id instead of ‘CUSTOMER_USER_ID_HERE’.

$user_id='CUSTOMER_USER_ID_HERE';
$customer_orders = get_posts( array(
                    'meta_key'    => '_customer_user',
                    'meta_value'  => $user_id,
                    'post_type'   => 'shop_order',
                    'post_status' => array_keys( wc_get_order_statuses() ),
                    'numberposts' => -1
                ));

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You can fetch all WooCommerce orders of a single customer by different parameter.
Here you can find all orders of a customer by email id.
Use the following to fetch all orders of a single customer in WooCommerce by email ID.
You have to replace customer email id instead of ‘CUSTOMER_EMAIL_ID_HERE’.

$billing_email='CUSTOMER_EMAIL_ID_HERE';
$customer_orders = get_posts( array(
                    'meta_key'    => '_billing_email',
                    'meta_value'  => $billing_email,
                    'post_type'   => 'shop_order',
                    'post_status' => array_keys( wc_get_order_statuses() ),
                    'numberposts' => -1
                ));

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There are several ways to get all WooCommerce Orders for a Customer.
Here you can get all Woocommerce orders for a customer by customer email id.
Use the following code to fecth WooCommerce orders for a customer.
The following code will fecth all orders for a current user.

$customer_orders = get_posts( array(    
    'meta_key'    => '_customer_user',
    'meta_value'  => get_current_user_id(),
    'post_type'   => 'shop_order',
    'post_status' => array_keys( wc_get_order_statuses() ),
    'numberposts' => -1
) );

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If you want to change default product visibility in woocommerce then add that following code in your functions.php file.
Here instead of “hidden” change your default visibility values.

function filter_woocommerce_product_visibility_default( $visible ) { 
    return "hidden"; 
	//return your default value here
}; 
add_filter( 'woocommerce_product_visibility_default', 'filter_woocommerce_product_visibility_default', 10, 1 );

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