PHP实现微信小程序支付完整版，可以借鉴！

var url = getApp().globalData.httpServer + 'api/buy/pay';
var userId = getApp().globalData.userId;
var totalMoney = this.data.totalMoney;
var cart = this.data.goods;
var param = {
cart: JSON.stringify(cart),
cartamount: totalMoney,
userid: userId,
payment: this.data.payment,
addressid: defaultAddress.id
};
var that = this;
util.http(url, param, function (ret) {
if (ret.data.code == 1) {
if (that.data.payment == 'balance') { // 余额支付
that.afterPaySuccess(ret.data.data);
} else { // 微信支付
wx.requestPayment({
timeStamp: ret.data.data.timeStamp,
nonceStr: ret.data.data.nonceStr,
package: ret.data.data.package,
signType: ret.data.data.signType,
paySign: ret.data.data.paySign,
'success': function (res) {
that.afterPaySuccess(ret.data.data.orderid);
},
'fail': function (res) {
console.log(res);
}
}) } } else {
util.showTip(ret.data.msg, '提交订单失败');
}
});

/**
* 网络请求
*/
function http(url, params, callback) {
wx.request({
url: url,
data: params,
success: function (res) {
callback(res);
}, fail: function (err) {
console.log(err);
}
});
}

public function pay()
{
$cart = I('cart', '', 'trim');
$cartAmount = I('cartamount');
$addressId = I('addressid', 0, 'intval');
$payment = I('payment', '', 'trim');
$userId = $this->userid; $cart = json_decode($cart, true);
if (empty($cart)) {
$result['msg'] = '购物车获取失败';
$result['code'] = 0;
$this->ajaxReturn($result);
} $totalMoney = 0;
foreach ($cart as $goods) {
$money = $goods['price']; // price
$selectCount = $goods['selectcount']; // price
$itemAmount = number_format($money * $selectCount, 2, '.', '');
$totalMoney += $itemAmount;
}
// 检查总金额是否一致
if ($totalMoney != $cartAmount) {
$result['msg'] = '总金额不匹配:' . $totalMoney;
$result['code'] = 0;
$this->ajaxReturn($result);
} // 获取用户地址
$address = M('MemberAddress')->where('userid=' . $userId . " and id=" . $addressId)->find();
if (empty($address)) {
$result['msg'] = '用户地址不存在';
$result['code'] = 0;
$this->ajaxReturn($result);
} // 用户信息
$user = M('Member')->where("id=" . $userId)->find();
if ($payment == 'balance') {
if ($user['amount'] < $cartAmount) {
$result['msg'] = '余额不足';
$result['code'] = 0;
$this->ajaxReturn($result);
}
} // 生成订单
$order['ordersn'] = $this->genOrdersn($user['id']);
$order['price'] = $cartAmount;
$order['addressid'] = $address['id'];
$order['addressinfo'] = serialize($address); //json_encode($address);
$order['longitude'] = $address['longitude'];
$order['latitude'] = $address['latitude'];
$order['addtime'] = time();
$order['status'] = 0;
$order['userid'] = $user['id'];
$order['paytype'] = $payment;
$order['paysn'] = '';
$order['paytime'] = time();
$orderId = M("Order")->add($order);
if ($orderId == 0) {
$result['msg'] = '创建订单失败';
$result['code'] = 0;
$this->ajaxReturn($result);
}
foreach ($cart as $goods) {
$orderGoods['orderid'] = $orderId;
$orderGoods['goodsid'] = $goods['id'];
$orderGoods['title'] = $goods['title'];
$orderGoods['price'] = $goods['price'];
$orderGoods['attr'] = $goods['attr'];
$orderGoods['pic'] = $goods['pic'];
$orderGoods['num'] = $goods['selectcount'];
M("OrderGoods")->add($orderGoods);
} if ($payment == 'balance') {
// 余额支付
$this->balancePay($cartAmount, $user['wxopenid'], $orderId);
} else if ($payment == 'weixin') {
// 微信支付
$this->weixinPay($cartAmount, $user['wxopenid'], $orderId, $order['ordersn']);
}
}

/**
* 微信支付
* @author 大脸猫脸大
* @param $cart
* @param $cartAmount
* @param $address
* @param $user
*/
private function weixinPay($cartAmount, $openId, $orderId, $orderSn)
{ import("Vendor.Wxpay.lib.WxPay#Api", "", ".php");
//订单号
$money = $cartAmount * 100;
$openid = $openId;
$input = new \WxPayUnifiedOrder();
$input->SetBody("迪克-商品");
$input->SetOut_trade_no("$orderSn");
$input->SetTotal_fee("$money");
$input->SetNotify_url("https://" . $_SERVER['HTTP_HOST'] . "/api/buy/payNotify");
$input->SetTrade_type("JSAPI");
$input->SetOpenid($openid);
$unifiedOrder = \WxPayApi::unifiedOrder($input); if ($unifiedOrder['result_code'] == 'SUCCESS' && $unifiedOrder['return_code'] == 'SUCCESS') {
$time = time();
$data['timeStamp'] = "$time"; //时间戳
$data['nonceStr'] = $unifiedOrder['nonce_str']; //随机字符串
$data['signType'] = 'MD5'; //签名算法，暂支持 MD5
$data['package'] = 'prepay_id=' . $unifiedOrder['prepay_id']; //统一下单接口返回的 prepay_id 参数值，提交格式如：prepay_id=*
$data['paySign'] = $this->genPaySign($unifiedOrder, $time);// 之前以为是$unifiedOrder['sign']; 后来发现是调用的这种方法. 签名方案参见微信公众号支付帮助文档; $data['out_trade_no'] = $orderSn;
$data['orderid'] = $orderId;
$return['code'] = 1;
$return['data'] = $data;
} else {
Log::write(var_export($unifiedOrder, true), Log::ERR, '', C('LOG_PATH')."wx_pay_".date('y_m_d').'.log');
$return['code'] = 0;
$return['msg'] = '微信支付失败';// $unifiedOrder['RETURN_MSG'];
}
$this->ajaxReturn($return);
}

/* 生成支付签名*/
private function genPaySign($unifiedOrder, $time)
{
$appId = \WxPayConfig::APPID;
$nonceStr = $unifiedOrder['nonce_str'];
$package = 'prepay_id=' . $unifiedOrder['prepay_id'];
$signType = "MD5";
$timeStamp = $time;
$key = \WxPayConfig::KEY; $sign = md5(sprintf("appId=%s&nonceStr=%s&package=%s&signType=%s&timeStamp=%s&key=%s", $appId, $nonceStr, $package, $signType, $timeStamp, $key));
}

/**
* 支付回调
* @author:大脸猫脸大
*/
public function payNotify()
{
import("Vendor.Wxpay.lib.WxPay#Data", "", ".php");
$xml = $GLOBALS['HTTP_RAW_POST_DATA'];
$val = \WxPayResults::Init($xml); if ($val['result_code'] == 'SUCCESS' && $val['return_code'] == 'SUCCESS') { $orderSn = $val['out_trade_no'];
$transactionId = $val['transaction_id'];
$data = array('paytype' => 'weixin', 'status' => '1', 'paytime' => time(), 'paysn' => $transactionId); M("Order")->where("ordersn='$orderSn'")->setField($data);
exit('<xml><return_code><![CDATA[SUCCESS]]></return_code><return_msg><![CDATA[OK]]></return_msg></xml>');
}else {
Log::write(var_export($val, true), Log::ERR, '', C('LOG_PATH')."wx_pay_notify_".date('y_m_d').'.log');
exit('<xml><return_code><![CDATA[FAIL]]></return_code><return_msg><![CDATA[OK]]></return_msg></xml>');
}
}

<xml><return_code><![CDATA[SUCCESS]]></return_code><return_msg><![CDATA[OK]]></return_msg></xml>