很多APP里都有支付，我们一般都是使用比较成熟且用户基数很大的第三方支付，比如支付宝和微信，为使用方便，我们一般都会进行封装，这样做的好处就是第三方SDK更换或者有变动，只对封装的类就行修改就好了。不多说了，直接上代码

使用示例代码

支付宝

PayOrderInfo *orderInfo = [[PayOrderInfo alloc] init];
orderInfo.payType = PayTypeAli;
//orderString由服务器返回
orderInfo.orderString = @"app_id=2015052600090779&biz_content=%7B%22timeout_express%22%3A%2230m%22%2C%22seller_id%22%3A%22%22%2C%22product_code%22%3A%22QUICK_MSECURITY_PAY%22%2C%22total_amount%22%3A%220.02%22%2C%22subject%22%3A%221%22%2C%22body%22%3A%22%E6%88%91%E6%98%AF%E6%B5%8B%E8%AF%95%E6%95%B0%E6%8D%AE%22%2C%22out_trade_no%22%3A%22314VYGIAGG7ZOYY%22%7D&charset=utf-8&method=alipay.trade.app.pay&sign_type=RSA2&timestamp=2016-08-15%2012%3A12%3A15&version=1.0&sign=MsbylYkCzlfYLy9PeRwUUIg9nZPeN9SfXPNavUCroGKR5Kqvx0nEnd3eRmKxJuthNUx4ERCXe552EV9PfwexqW%2B1wbKOdYtDIb4%2B7PL3Pc94RZL0zKaWcaY3tSL89%2FuAVUsQuFqEJdhIukuKygrXucvejOUgTCfoUdwTi7z%2BZzQ%3D";
orderInfo.scheme = @"alipay";
[[PayService defaultService] payOrder:orderInfo result:^(BOOL success, NSString *data) {
if (success) {
//在此向自己的服务器请求验证支付是否成功
}
}];
[[PayService defaultService] setHandleBackToAppByUnusualWay:^{
//通过左上角或者其他非正常途径返回APP
//在此向自己的服务器请求验证支付是否成功
NSLog(@"支付验证");
}];

微信

PayOrderInfo *orderInfo = [[PayOrderInfo alloc] init];
orderInfo.payType = PayTypeWX;
orderInfo.openID = @"wxd930ea5d5a258f4f";
orderInfo.partnerId = @"10000100";
orderInfo.prepayId= @"1101000000140415649af9fc314aa427";
orderInfo.package = @"Sign=WXPay";
orderInfo.nonceStr= @"a462b76e7436e98e0ed6e13c64b4fd1c";
orderInfo.timeStamp= @1397527777;
orderInfo.sign= @"582282D72DD2B03AD892830965F428CB16E7A256";
[[PayService defaultService] payOrder:orderInfo result:^(BOOL success, NSString *data) {
if (success) {
//在此向自己的服务器请求验证支付是否成功
}
}];
[[PayService defaultService] setHandleBackToAppByUnusualWay:^{
//通过左上角或者其他非正常途径返回APP
//在此向自己的服务器请求验证支付是否成功
NSLog(@"支付验证");
}];

银联

PayOrderInfo *orderInfo = [[PayOrderInfo alloc] init];
orderInfo.payType = PayTypeUnion;
orderInfo.scheme = @"unionpay";
//orderString由服务器返回
orderInfo.orderString = @"app_id=2015052600090779&biz_content=%7B%22timeout_express%22%3A%2230m%22%2C%22seller_id%22%3A%22%22%2C%22product_code%22%3A%22QUICK_MSECURITY_PAY%22%2C%22total_amount%22%3A%220.02%22%2C%22subject%22%3A%221%22%2C%22body%22%3A%22%E6%88%91%E6%98%AF%E6%B5%8B%E8%AF%95%E6%95%B0%E6%8D%AE%22%2C%22out_trade_no%22%3A%22314VYGIAGG7ZOYY%22%7D&charset=utf-8&method=alipay.trade.app.pay&sign_type=RSA2&timestamp=2016-08-15%2012%3A12%3A15&version=1.0&sign=MsbylYkCzlfYLy9PeRwUUIg9nZPeN9SfXPNavUCroGKR5Kqvx0nEnd3eRmKxJuthNUx4ERCXe552EV9PfwexqW%2B1wbKOdYtDIb4%2B7PL3Pc94RZL0zKaWcaY3tSL89%2FuAVUsQuFqEJdhIukuKygrXucvejOUgTCfoUdwTi7z%2BZzQ%3D";
orderInfo.mode= @"01";
orderInfo.viewController = self;
[[PayService defaultService] payOrder:orderInfo result:^(BOOL success, NSString *data) {
if (success) {
//在此向自己的服务器请求验证支付是否成功
}
}];
[[PayService defaultService] setHandleBackToAppByUnusualWay:^{
//通过左上角或者其他非正常途径返回APP
//在此向自己的服务器请求验证支付是否成功
NSLog(@"支付验证");
}];

Apple Pay

PayOrderInfo *orderInfo = [[PayOrderInfo alloc] init];
orderInfo.payType = PayTypeApple;
orderInfo.merchantIdentifier = @"";
orderInfo.supportBankCards = @[PKPaymentNetworkVisa,PKPaymentNetworkMasterCard];
PayShipMethod *method = [[PayShipMethod alloc] init];
method.name = @"顺丰快递";
method.price = @"20";
method.identifier = @"sf";
method.detail = @"之所以快，是因为你掏的钱多";
orderInfo.shipMethods = @[method];
PaySummaryItem *item = [[PaySummaryItem alloc] init];
item.name = @"iPhone X";
item.price = @"8868";
PaySummaryItem *itemTotal = [[PaySummaryItem alloc] init];
itemTotal.name = @"App Store";
itemTotal.price = @"8868";
orderInfo.payTypeSummaryItems = @[item,itemTotal];
orderInfo.applicationData = @"id=apple-pay";
orderInfo.viewController = self;
[[PayService defaultService] payOrder:orderInfo result:nil];
[[PayService defaultService] setHandleApplePayAuthorizePayment:^BOOL(PKPayment *payment) {
PKPaymentToken *token = payment.token;
PKPaymentMethod *method = token.paymentMethod;
NSLog(@"PKPaymentMethod==%@",method);
//在此根据token向自己的服务器请求验证支付是否成功
return YES;
}];

以上是具体使用方法，如果想了解更具体的使用方法和文档说明，可以下载Demo。