ecshop购物车页面使用ajax更新商品数量、小计、总价，点击加号和减号

第一步

我先把 我的购物车页面flow.dwt的商品列表部分的代码贴出来，这样比较起来方便一点

<div class="flowBox">
<h6><span>{$lang.goods_list}</span></h6>

<div class="flowBox_in">
<form id="formCart" name="formCart" method="post" action="flow.php">
<table width="99%" align="center" border="0" cellpadding="5" cellspacing="1" bgcolor="#aacded">
<tr>
<th bgcolor="#ebf4fb">{$lang.goods_name}</th>

<!-- {if $show_marketprice} 显示市场价 -->
<th bgcolor="#ebf4fb">{$lang.market_prices}</th>
<!-- {/if} -->
<th bgcolor="#ebf4fb">{$lang.shop_prices}</th>
<th bgcolor="#ebf4fb">{$lang.number}</th>
<th bgcolor="#ebf4fb">{$lang.subtotal}</th>
<th bgcolor="#ebf4fb">{$lang.handle}</th>
</tr>
<!-- {foreach from=$goods_list item=goods} -->
<tr id="tr_goods_{$goods.rec_id}">
<td bgcolor="#ffffff" align="center">
<!-- {if $goods.goods_id gt 0 && $goods.extension_code neq 'package_buy'} 商品 -->
<!-- {if $show_goods_thumb eq 1} -->
<a href="goods.php?id={$goods.goods_id}" target="_blank" class="f6">{$goods.goods_name}</a>
<!-- {elseif $show_goods_thumb eq 2} -->
<a href="goods.php?id={$goods.goods_id}" target="_blank"><img style="width:50px" src="{$goods.goods_thumb}" border="0" title="{$goods.goods_name|escape:html}" /></a>
<!-- {else} -->
<a href="goods.php?id={$goods.goods_id}" target="_blank"><img style="width:50px" src="{$goods.goods_thumb}" border="0" title="{$goods.goods_name|escape:html}" /></a><br />
<a href="goods.php?id={$goods.goods_id}" target="_blank" class="f6">{$goods.goods_name}</a>
<!-- {/if} -->
<!-- {if $goods.parent_id gt 0} 配件 -->
<span style="color:#FF0000">（{$lang.accessories}）</span>
<!-- {/if} -->
<!-- {if $goods.is_gift gt 0} 赠品 -->
<span style="color:#FF0000">（{$lang.largess}）</span>
<!-- {/if} -->
<!-- {elseif $goods.goods_id gt 0 && $goods.extension_code eq 'package_buy'} -->
<a href="javascript:void(0)" onclick="setSuitShow({$goods.goods_id})" class="f6">{$goods.goods_name}<span style="color:#FF0000;">（{$lang.remark_package}）</span></a>
<div id="suit_{$goods.goods_id}" style="display:none">
<!-- {foreach from=$goods.package_goods_list item=package_goods_list} -->
<a href="goods.php?id={$package_goods_list.goods_id}" target="_blank" class="f6">{$package_goods_list.goods_name}</a><br />
<!-- {/foreach} -->
</div>
<!-- {else} 优惠活动 -->
{$goods.goods_name}
<!-- {/if} -->
</td>

<!-- {if $show_marketprice} 显示市场价 -->
<td align="center" bgcolor="#ffffff">{$goods.market_price}</td>
<!-- {/if} -->
<td align="center" bgcolor="#ffffff">{$goods.goods_price}</td>
<td align="center" bgcolor="#ffffff">
<!-- {if $goods.goods_id gt 0 && $goods.is_gift eq 0 && $goods.parent_id eq 0} 普通商品可修改数量 -->
<a onclick="changenum({$goods.rec_id},-1)" style="height:12px; color:#000; line-height:12px; padding:0px 4px; background:#fff; border:1px #eee solid; display:inline-block;" href="javascript:void(0)" >-</a>
<input type="text" name="goods_number[{$goods.rec_id}]" id="goods_number_{$goods.rec_id}" value="{$goods.goods_number}" size="3"class="inputBg" style="text-align:center " onchange="change_goods_number({$goods.rec_id},this.value)"/>
<a onclick="changenum({$goods.rec_id},1)" style="height:12px; color:#000; line-height:12px; padding:0px 4px; background:#fff; border:1px #eee solid; display:inline-block;" href="javascript:void(0)" >+</a>
<!-- {else} -->
{$goods.goods_number}
<!-- {/if} -->
</td>

<td align="center" bgcolor="#ffffff" id="goods_subtotal_{$goods.rec_id}">
<span>{$goods.subtotal}</span>
</td>

<td align="center" bgcolor="#ffffff">
<a href="javascript:if (confirm('{$lang.drop_goods_confirm}')) location.href='flow.php?step=drop_goods&id={$goods.rec_id}'; " class="f6">{$lang.drop}</a>
<!-- {if $smarty.session.user_id gt 0 && $goods.extension_code neq 'package_buy'} 如果登录了，可以加入收藏 -->
<a href="javascript:if (confirm('{$lang.drop_goods_confirm}')) location.href='flow.php?step=drop_to_collect&id={$goods.rec_id}'; " class="f6">{$lang.drop_to_collect}</a>
<!-- {/if} -->
</td>
</tr>
<!-- {/foreach} -->
</table>
<table width="99%" align="center" border="0" cellpadding="5" cellspacing="1" bgcolor="#aacded">
<tr>
<td bgcolor="#ebf4fb" id="total_desc">
<!-- {if $discount gt 0} -->{$your_discount}<br /><!-- {/if} -->
{$shopping_money}<!-- {if $show_marketprice} -->，{$market_price_desc}<!-- {/if} -->
</td>
<td align="right" bgcolor="#ebf4fb">
<input type="button" value="{$lang.clear_cart}" class="bnt_blue_1" onclick="location.href='flow.php?step=clear'" />

</td>
</tr>
</table>

第二步

我把js函数写出来

<script type="text/javascript">
function changenum(rec_id, diff)
{
var goods_number =Number($$('goods_number_' + rec_id).value) + Number(diff);
change_goods_number(rec_id,goods_number);
}
function change_goods_number(rec_id, goods_number)
{
if(goods_number >= 1){
Ajax.call('flow.php?step=ajax_update_cart', 'rec_id=' + rec_id +'&goods_number=' + goods_number, change_goods_number_response, 'POST','JSON');
}
}
function change_goods_number_response(result)
{
if (result.error == 0)
{
var rec_id = result.rec_id;

4000
var tr_goods = 'tr_goods_' + rec_id;

$$('goods_number_' +rec_id).value = result.goods_number;//更新数量
$$('goods_subtotal_' +rec_id).innerHTML = result.goods_subtotal;//更新小计
if (result.goods_number <= 0)
{// 数量为零则隐藏所在行
$$(tr_goods).style.display = 'none';
$$(tr_goods).innerHTML = '';
}
$$('total_desc').innerHTML =result.total_desc;//更新合计
if ($$('ECS_CARTINFO'))
{//更新购物车数量
$$('ECS_CARTINFO').innerHTML = result.cart_info;
}
}
else if (result.message != '')
{
alert(result.message);
}
}
</script>

以上两部分是flow.dwt页面全部的代码

第三步

也就是要处理ajax请求的php代码，是flow.php文件

//-- 更新购物车商品数量

/*------------------------------------------------------ */

elseif ($_REQUEST['step']== 'ajax_update_cart')
{
require_once(ROOT_PATH .'includes/cls_json.php');
$json = new JSON();
$result = array('error' => 0, 'message'=> '');
if (isset($_POST['rec_id']) && isset($_POST['goods_number']))
{
$key = $_POST['rec_id'];
$val = $_POST['goods_number'];
$val = intval(make_semiangle($val));
if ($val <= 0 && !is_numeric($key))
{
$result['error'] = 99;
$result['message'] = '';
die($json->encode($result));
}

//查询：
$sql = "SELECT `goods_id`, `goods_attr_id`,`product_id`, `extension_code` FROM" .$GLOBALS['ecs']->table('cart').
" WHERE rec_id='$key' AND session_id='" . SESS_ID . "'";
$goods =$GLOBALS['db']->getRow($sql);

$sql = "SELECT g.goods_name,g.goods_number ".
"FROM ".$GLOBALS['ecs']->table('goods'). " AS g, ".
$GLOBALS['ecs']->table('cart'). " AS c ".
"WHERE g.goods_id =c.goods_id AND c.rec_id = '$key'";
$row = $GLOBALS['db']->getRow($sql);

//查询：系统启用了库存，检查输入的商品数量是否有效
if(intval($GLOBALS['_CFG']['use_storage']) > 0 && $goods['extension_code'] != 'package_buy')
{
if ($row['goods_number'] < $val)
{
$result['error'] = 1;
$result['message'] =sprintf($GLOBALS['_LANG']['stock_insufficiency'], $row['goods_name'],$row['goods_number'], $row['goods_number']);
die($json->encode($result));
}
/* 是货品*/
$goods['product_id'] = trim($goods['product_id']);
if (!empty($goods['product_id']))
{
$sql = "SELECT product_number FROM " .$GLOBALS['ecs']->table('products'). " WHERE goods_id = '" . $goods['goods_id'] . "' AND product_id = '" .$goods['product_id'] . "'";

$product_number =$GLOBALS['db']->getOne($sql);
if ($product_number < $val)
{
$result['error'] = 2;
$result['message'] =sprintf($GLOBALS['_LANG']['stock_insufficiency'], $row['goods_name'],
$product_number['product_number'], $product_number['product_number']);
die($json->encode($result));
}
}
}
elseif (intval($GLOBALS['_CFG']['use_storage'])> 0 && $goods['extension_code'] == 'package_buy')
{
if(judge_package_stock($goods['goods_id'], $val))
{
$result['error'] = 3;
$result['message'] =$GLOBALS['_LANG']['package_stock_insufficiency'];
die($json->encode($result));
}
}

/* 查询：检查该项是否为基本件 以及是否存在配件*/
/* 此处配件是指添加商品时附加的并且是设置了优惠价格的配件 此类配件都有parent_idgoods_number为1 */
$sql = "SELECT b.goods_number,b.rec_id FROM ".$GLOBALS['ecs']->table('cart') . " a, ".$GLOBALS['ecs']->table('cart') . " b WHERE a.rec_id = '$key' AND a.session_id = '" .SESS_ID . "' AND a.extension_code <> 'package_buy' AND b.parent_id = a.goods_id AND b.session_id = '" .SESS_ID . "'";

$offers_accessories_res =$GLOBALS['db']->query($sql);
//订货数量大于0
if ($val > 0)
{
/* 判断是否为超出数量的优惠价格的配件 删除*/
$row_num = 1;
while ($offers_accessories_row =$GLOBALS['db']->fetchRow($offers_accessories_res))
{
if ($row_num > $val)
{
$sql = "DELETE FROM" . $GLOBALS['ecs']->table('cart') .
" WHERE session_id = '" . SESS_ID . "' " .
"AND rec_id ='" . $offers_accessories_row['rec_id'] ."' LIMIT 1";
$GLOBALS['db']->query($sql);
}

$row_num ++;
}

/* 处理超值礼包*/
if ($goods['extension_code'] =='package_buy')
{
//更新购物车中的商品数量
$sql = "UPDATE ".$GLOBALS['ecs']->table('cart').
" SET goods_number= '$val' WHERE rec_id='$key' AND session_id='" . SESS_ID . "'";
}
/* 处理普通商品或非优惠的配件*/
else
{
$attr_id    = empty($goods['goods_attr_id']) ? array(): explode(',', $goods['goods_attr_id']);
$goods_price =get_final_price($goods['goods_id'], $val, true, $attr_id);

//更新购物车中的商品数量
$sql = "UPDATE ".$GLOBALS['ecs']->table('cart').
" SET goods_number= '$val', goods_price = '$goods_price' WHERE rec_id='$key' AND session_id='" . SESS_ID . "'";
}
}
//订货数量等于0
else
{
/* 如果是基本件并且有优惠价格的配件则删除优惠价格的配件*/
while ($offers_accessories_row =$GLOBALS['db']->fetchRow($offers_accessories_res))
{
$sql = "DELETE FROM ". $GLOBALS['ecs']->table('cart') .
" WHERE session_id= '" . SESS_ID . "' " .
"AND rec_id ='" . $offers_accessories_row['rec_id'] ."' LIMIT 1";
$GLOBALS['db']->query($sql);
}

$sql = "DELETE FROM ".$GLOBALS['ecs']->table('cart').
" WHERE rec_id='$key' AND session_id='" .SESS_ID. "'";
}

$GLOBALS['db']->query($sql);

/* 删除所有赠品*/
$sql = "DELETE FROM " .$GLOBALS['ecs']->table('cart') . " WHERE session_id = '" .SESS_ID."' AND is_gift <> 0";
$GLOBALS['db']->query($sql);

$result['rec_id'] = $key;
$result['goods_number'] = $val;
$result['goods_subtotal'] = '';
$result['total_desc'] = '';
$result['cart_info'] =insert_cart_info();
/* 计算合计*/
$cart_goods = get_cart_goods();
foreach ($cart_goods['goods_list'] as $goods )
{
if ($goods['rec_id'] == $key)
{
$result['goods_subtotal'] =$goods['subtotal'];
break;
}
}
$shopping_money = sprintf($_LANG['shopping_money'], $cart_goods['total']['goods_price']);
$market_price_desc = sprintf($_LANG['than_market_price'],$cart_goods['total']['market_price'],$cart_goods['total']['saving'], $cart_goods['total']['save_rate']);

/* 计算折扣*/
$discount = compute_discount();
$favour_name = empty($discount['name'])? '' : join(',', $discount['name']);
$your_discount =sprintf($_LANG['your_discount'], $favour_name,price_format($discount['discount']));

if ($discount['discount'] > 0)
{
$result['total_desc'] .=$your_discount . '<br />';
}
$result['total_desc'] .=$shopping_money;
if ($_CFG['show_marketprice'])
{
$result['total_desc'] .= '，' .$market_price_desc;
}
die($json->encode($result));
}
else
{
$result['error'] = 100;
$result['message'] = '';
die($json->encode($result));
}
}