I am customizing woo-commerce plugin to add product from the front end into the cart. I have written the function in functions.php, but i am getting a Fatal error. Any body have any idea how to resolve it?


   

    if (isset($_POST["addcustomcarts"]))
            {
           echo $_SERVER[QUERY_STRING];
          // echo $_SERVER[REQUEST_URI];
            echo "i am in if";
            //exit();
        add_filter('woocommerce_before_cart', 'customcart');
        
        function customcart() { 
           echo "i am in function";
            
        //global $woocommerce;
        
        $my_post = array(
          'post_title'    => 'My post',
          'post_content'  => 'This is my post.',
          'post_status'   => 'publish',
          'post_author'   => 1,
          'post_type'     =>'product'
          
        );
        
        
        // Insert the post into the database
         $product_ID=wp_insert_post( $my_post );
         
         add_post_meta($product_ID, '_regular_price', 100, $unique);
         add_post_meta($product_ID, '_price', 100, $unique);
          add_post_meta($product_ID, '_stock_status', 'instock', $unique);
         
         
          //Getting error on this line.
          $woocommerce->cart->add_to_cart( $product_ID, $quantity=1 );
         
        
         
        
         exit( wp_redirect( home_url( "cart" ) ) );
        }
        
        customcart();
          }

Getting this error-->
 Fatal error: Call to a member function add_to_cart() on a non-object in    C:\wamp\www\cutting-edge_server\wordpress_theme\wp-content\themes\cutting_age\responsive\functions.php on line 56