Add Tax Exempt form on checkout in woocommerce

Alright, I finally figured it out in case anyone is interested.

In my plugin, I made a form after the order notes by hooking in to this function: 'woocommerce_before_order_notes'

add_action('woocommerce_before_order_notes', array(&$this, 'taxexempt_before_order_notes') );

my 'taxexempt_before_order_notes' function contained:

function taxexempt_before_order_notes( $checkout ) {        echo '<div style="clear: both"></div>        <h3>Tax Exempt Details</h3>';        woocommerce_form_field( 'tax_exempt_checkbox', array(            'type'          => 'checkbox',            'class'         => array('tiri taxexempt'),array( 'form-row-wide', 'address-field' ),            'label'         => __('Tax Exempt'),            ), $checkout->get_value( 'tax_exempt_checkbox' ));        woocommerce_form_field( 'tax_exempt_name', array(            'type'          => 'text',            'class'         => array('form-row-first', 'tiri', 'taxexempt', 'textbox', 'hidden'),            'label'         => __('Tax Exempt Name'),            ), $checkout->get_value( 'tax_exempt_name' ));        woocommerce_form_field( 'tax_exempt_id', array(            'type'          => 'text',            'class'         => array('form-row-last', 'tiri', 'taxexempt', 'textbox', 'hidden', 'update_totals_on_change'),            'label'         => __('Tax Exempt Id'),            ), $checkout->get_value( 'tax_exempt_id' ));    }

Then the most important woocommerce function to hook was: 'woocommerce_checkout_update_order_review'

add_action( 'woocommerce_checkout_update_order_review', array(&$this, 'taxexempt_checkout_update_order_review' ));function taxexempt_checkout_update_order_review( $post_data ) {        global $woocommerce;        $woocommerce->customer->set_is_vat_exempt(FALSE);        parse_str($post_data);        if ( isset($tax_exempt_checkbox) && isset($tax_exempt_id) && $tax_exempt_checkbox == '1' && !empty($tax_exempt_id))            $woocommerce->customer->set_is_vat_exempt(true);                    }

I simply parsed out the $post_data that is the serialized form data from the checkout.js file in woocommerce and checked if my part of the form was filled out correctly.

If it was, then I would set the tax exempt for the user.

The accepted solution didn't work for me, but I modified it to use the following:

//=============================================================================// ADD TAX EXEMPT CHECKMARK// =============================================================================add_action( 'woocommerce_after_order_notes', 'qd_tax_exempt');function qd_tax_exempt( $checkout ) {  echo '<div id="qd-tax-exempt"><h3>'.__('Tax Exempt').'</h3>';  woocommerce_form_field( 'shipping_method_tax_exempt', array(      'type'          => 'checkbox',      'class'         => array(),      'label'         => __('My organization is tax exempt.'),      'required'  => false,      ), $checkout->get_value( 'shipping_method_tax_exempt' ));  echo '</div>';}add_action( 'woocommerce_checkout_update_order_review', 'taxexempt_checkout_update_order_review');function taxexempt_checkout_update_order_review( $post_data ) {  global $woocommerce;  $woocommerce->customer->set_is_vat_exempt(FALSE);  parse_str($post_data);  if ( isset($shipping_method_tax_exempt) && $shipping_method_tax_exempt == '1')    $woocommerce->customer->set_is_vat_exempt(true);                }

The key here is understanding that any field with a name that starts with shipping_method is going to inherit this updating order functionality (which was the part that didn't work for me). I found this answer at http://www.affectivia.com/blog/have-a-checkbox-on-the-checkout-page-which-updates-the-order-totals/

After a long search I found that there is a method for the cart object called remove_taxes() .So, after setting a user meta for the tax exempt users, this cancels the tax totals.

function remove_tax_for_exempt( $cart ) {    global $current_user;    $ok_taxexp = get_the_author_meta( 'granted_taxexempt', $current_user->ID );    if ($ok_taxexp){ // now 0 the tax if user is tax exempt        $cart->remove_taxes();    }    return $cart;} add_action( 'woocommerce_calculate_totals', 'remove_tax_for_exempt' );