我有一个类叫做ot_lev_discount
在这个类中，我有一个函数: <?php
/*
<<<<<<< ot_lev_discount.php
$Id: ot_lev_discount.php,v 1.0 2002/04/08 01:13:43 hpdl Exp $
=======
$Id: ot_lev_discount.php,v 1.3 2002/09/04 22:49:11 wilt Exp $
$Id: ot_lev_discount.php,v 2.4 2006/02/28 12:10:01 maniac101 Exp $
modified to calc discount correctly when tax is included in discount
>>>>>>> 2.4
osCommerce, Open Source E-Commerce Solutions
http://www.oscommerce.com
Copyright (c) 2002 osCommerce
Released under the GNU General Public License
*/
class ot_lev_discount {
var $title, $output;
function ot_lev_discount() {
$this->code = 'ot_lev_discount';
$this->title = MODULE_LEV_DISCOUNT_TITLE;
$this->description = MODULE_LEV_DISCOUNT_DESCRIPTION;
$this->enabled = MODULE_LEV_DISCOUNT_STATUS;
$this->sort_order = MODULE_LEV_DISCOUNT_SORT_ORDER;
$this->include_shipping = MODULE_LEV_DISCOUNT_INC_SHIPPING;
$this->include_tax = MODULE_LEV_DISCOUNT_INC_TAX;
$this->calculate_tax = MODULE_LEV_DISCOUNT_CALC_TAX;
$this->table = MODULE_LEV_DISCOUNT_TABLE;
// $this->credit_class = true;
$this->output = array();
}
function process() {
global $order, $ot_subtotal, $currencies;
$od_amount = $this->calculate_credit($this->get_order_total());
if ($od_amount>0) {
$this->deduction = $od_amount;
$this->output[] = array('title' => $this->title . ':',
'text' => '<b>' . $currencies->format($od_amount) . '</b>',
'value' => $od_amount);
$order->info['total'] = $order->info['total'] - $od_amount;
if ($this->sort_order < $ot_subtotal->sort_order) {
$order->info['subtotal'] = $order->info['subtotal'] - $od_amount;
}
}
}
function calculate_credit($amount) {
global $order;
$od_amount=0;
$table_cost = split("[:,]" , MODULE_LEV_DISCOUNT_TABLE);
for ($i = 0; $i < count($table_cost); $i+=2) {
if ($amount >= $table_cost[$i]) {
$od_pc = $table_cost[$i+1];
}
}
// Calculate tax reduction if necessary
if($this->calculate_tax == 'true') {
// Calculate main tax reduction
$tod_amount = round($order->info['tax']*10)/10*$od_pc/100;
$order->info['tax'] = $order->info['tax'] - $tod_amount;
// Calculate tax group deductions
reset($order->info['tax_groups']);
while (list($key, $value) = each($order->info['tax_groups'])) {
$god_amount = round($value*10)/10*$od_pc/100;
$order->info['tax_groups'][$key] = $order->info['tax_groups'][$key] - $god_amount;
}
}
$od_amount = $od_pc;
// if you want to use %age instead of flat amount: $od_amount = round($amount*10)/10*$od_pc/100;
// $od_amount = $od_amount + $tod_amount;
// maniac101 above line was adding tax back into discount incorrectly for me
return $od_amount;
}
function get_order_total() {
global $order, $cart;
$order_total = $order->info['total'];
// Check if gift voucher is in cart and adjust total
$products = $cart->get_products();
for ($i=0; $i<sizeof($products); $i++) {
$t_prid = tep_get_prid($products[$i]['id']);
$gv_query = tep_db_query("select products_price, products_tax_class_id, products_model from " . TABLE_PRODUCTS . " where products_id = '" . $t_prid . "'");
$gv_result = tep_db_fetch_array($gv_query);
if (ereg('^GIFT', addslashes($gv_result['products_model']))) {
$qty = $cart->get_quantity($t_prid);
$products_tax = tep_get_tax_rate($gv_result['products_tax_class_id']);
if ($this->include_tax =='false') {
$gv_amount = $gv_result['products_price'] * $qty;
} else {
$gv_amount = ($gv_result['products_price'] + tep_calculate_tax($gv_result['products_price'],$products_tax)) * $qty;
}
$order_total=$order_total - $gv_amount;
}
}
if ($this->include_tax == 'false') $order_total=$order_total-$order->info['tax'];
if ($this->include_shipping == 'false') $order_total=$order_total-$order->info['shipping_cost'];
return $order_total;
}
function check() {
if (!isset($this->check)) {
$check_query = tep_db_query("select configuration_value from " . TABLE_CONFIGURATION . " where configuration_key = 'MODULE_LEV_DISCOUNT_STATUS'");
$this->check = tep_db_num_rows($check_query);
}
return $this->check;
}
function keys() {
return array('MODULE_LEV_DISCOUNT_STATUS', 'MODULE_LEV_DISCOUNT_SORT_ORDER','MODULE_LEV_DISCOUNT_TABLE', 'MODULE_LEV_DISCOUNT_INC_SHIPPING', 'MODULE_LEV_DISCOUNT_INC_TAX','MODULE_LEV_DISCOUNT_CALC_TAX');
}
function install() {
tep_db_query("insert into " . TABLE_CONFIGURATION . " (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, set_function, date_added) values ('Display Total', 'MODULE_LEV_DISCOUNT_STATUS', 'true', 'Do you want to enable the Order Discount?', '6', '1','tep_cfg_select_option(array(''true'', ''false''), ', now())");
tep_db_query("insert into " . TABLE_CONFIGURATION . " (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, date_added) values ('Sort Order', 'MODULE_LEV_DISCOUNT_SORT_ORDER', '999', 'Sort order of display.', '6', '2', now())");
tep_db_query("insert into " . TABLE_CONFIGURATION . " (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, set_function ,date_added) values ('Include Shipping', 'MODULE_LEV_DISCOUNT_INC_SHIPPING', 'true', 'Include Shipping in calculation', '6', '3', 'tep_cfg_select_option(array(''true'', ''false''), ', now())");
tep_db_query("insert into " . TABLE_CONFIGURATION . " (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, set_function ,date_added) values ('Include Tax', 'MODULE_LEV_DISCOUNT_INC_TAX', 'true', 'Include Tax in calculation.', '6', '4','tep_cfg_select_option(array(''true'', ''false''), ', now())");
tep_db_query("insert into " . TABLE_CONFIGURATION . " (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, set_function ,date_added) values ('Calculate Tax', 'MODULE_LEV_DISCOUNT_CALC_TAX', 'false', 'Re-calculate Tax on discounted amount.', '6', '5','tep_cfg_select_option(array(''true'', ''false''), ', now())");
tep_db_query("insert into " . TABLE_CONFIGURATION . " (configuration_title, configuration_key, configuration_value, configuration_description, configuration_group_id, sort_order, date_added) values ('Discount Percentage', 'MODULE_LEV_DISCOUNT_TABLE', '100:7.5,250:10,500:12.5,1000:15', 'Set the price breaks and discount percentages', '6', '6', now())");
}
function remove() {
$keys = '';
$keys_array = $this->keys();
for ($i=0; $i<sizeof($keys_array); $i++) {
$keys .= "'" . $keys_array[$i] . "',";
}
$keys = substr($keys, 0, -1);
tep_db_query("delete from " . TABLE_CONFIGURATION . " where configuration_key in (" . $keys . ")");
}
}
?>
我想从另一个php文件回显$od_amount变量，所以我做了以下操作，但无济于事:
require(DIR_WS_MODULES . 'order_total/ot_lev_discount.php');
$ot_lev_discount = new ot_lev_discount();
echo $ot_lev_discount->od_amount;
我似乎能够以这种方式调用类全局变量，但不是类函数中的全局变量。
global并没有使变量成为类的属性，它只是告诉这个值可以在类的任何方法中使用。
你可以绕过这个，看下面的例子
通过调用$ot_lev_discount->od_amount，您试图获得您的类的od_amount属性，但您的类没有一个。
你需要这样修改你的类:
class ot_lev_discount {
...
public $od_amount;
function calculate_credit($amount)
{
...
$this->od_amount = $od_amount;
return $od_amount;
}
}
这样，您将能够使用$ot_lev_discount->od_amount访问属性。当然，它的值将为空，除非你调用$ot_lev_discount->calculate_credit()函数。
花点时间阅读有关类、对象及其属性和变量作用域的文档。它应该对您所面临的问题有一些启发(这些是一般的面向对象编程主题，而不仅仅是与PHP有关)。
函数内的变量具有该函数的局部作用域，不能从函数外部调用。您可以通过以下操作将这些变量的作用域设置为类级和公共的:
class ot_lev_discount {
public $od_amount;
....
}
然后你可以这样访问变量:
$var = new ot_lev_discount();
$var->od_amount;
尽管在这种情况下，每次创建新对象时，该对象都有自己的od_amount变量，该变量与同一类的另一个对象不同，除非对其执行相同的计算，否则该变量的值不会相同。
或者，调用函数并获取返回值。