支付宝Payto接口的c#.net实现

如果还不了解支付宝payto原理的可以在这里下文档和演示   http://dev.alipay.com/download/alipay_docs.rar
集成演示指南： http://dev.alipay.com/download/yanshi.zip 
        
       它现在这种支付方式比较多象网银在线等使用的方法都是url验证，就是通过url参数和一个这些url参数的md5编码来确认这个连接的正确性，支付宝在你购买成功后跳转自定义连接的时候会传2次过来，第一次是数据底层请求，第二次是web请求，而只有第一次有验证码，这个只能通过记录下来才看的到，因为两次请求间隔很小，如果光显示的话最后的结果是被第二次覆盖了的。所以在接收的时候就要设定接收条件，一种是没有notify_type参数的，一种是有的。

         我们先来看一下创建一个连接地址

t1 = ConfigurationSettings.AppSettings[ " interface " ]; // 支付接口,就是给的一个连接地址
            t2 = ConfigurationSettings.AppSettings[ " account " ]; // 支付宝帐户你的帐户
            t3 = ConfigurationSettings.AppSettings[ " password " ]; // 安全校验码，设置的商家验证码
            t4 = " images/logo_zfbsmall.gif " ; // 按钮图片地址
            t5 = " test " ; // 悬停说明
            cmd = " 0001 " ; // 默认
            subject = " item " ; // 商品名称
            body = " decrip " ; // 描述
            order_no = ; // 定单号，用户自己生成，方便自己管理                prices=100; // 价格0.01～50000.00
            rurl = " http://www.xxx.com/ " ; // 商品展示网址
            types = " 1 " ; // 1：商品购买2：服务购买3：网络拍卖4：捐赠
            number = " 1 " ; // 购买数量
            transport = " 3 " ; // 1：平邮2：快递3：虚拟物品
            ordinary_fee = "" ; // 平邮运费
            express_fee = "" ; // 快递运费
            readonlys = " true " ; // 交易信息是否只读
            buyer_msg = "" ; // 买家给卖家的留言
            buyer = "" ; // 买家Email
            buyer_name = "" ; // 买家姓名
            buyer_address = "" ; // 买家地址
            buyer_zipcode = "" ; // 买家邮编
            buyer_tel = "" ; // 买家电话号码
            buyer_mobile = "" ; // 买家手机号码
            partner = ConfigurationSettings.AppSettings[ " partenid " ]; // 合作伙伴ID,这个是固定的

上面就是要提供得基本信息，然后就是生成支付宝得连接，也就是给支付宝提供一条带验证的购买信息。

public   string  creatAlipayItemURL( string  t1, string  t2, string  t3, string  t4, string  t5, string  cmd, string  subject, string  body, string  order_no, string  prices, string  rurl, string  types, string  number, string  transport, string  ordinary_fee, string  express_fee, string  readonlys, string  buyer_msg, string  buyer, string  buyer_name, string  buyer_address, string  buyer_zipcode, string  buyer_tel, string  buyer_mobile, string  partner)
        {
             string  itemURL,str2CreateAc,acCode;
             string  INTERFACE_URL,sellerEmail,keyCode,imgsrc,imgtitle,AlipayItemURL;
             // 初始化各必要变量
            INTERFACE_URL = t1 + t2; // 支付接口
            sellerEmail = t2; // 商户支付宝账户（改成你自己的）
            keyCode = t3; // 安全校验码（改成你自己的）
            imgsrc = t4; // 支付宝按钮图片
            imgtitle = t5; // 按钮悬停说明

            str2CreateAc = " cmd "   +  cmd  +   " subject "   +  subject;
            str2CreateAc = str2CreateAc  +   " body "   +  body;
            str2CreateAc = str2CreateAc  +   " order_no "   +  order_no;
            str2CreateAc = str2CreateAc  +   " price "   +  prices;
             // str2CreateAc=str2CreateAc + "url" + rurl;
            str2CreateAc = str2CreateAc  +   " type "   +  types;
            str2CreateAc = str2CreateAc  +   " number "   +  number;
            str2CreateAc = str2CreateAc  +   " transport "   +  transport;
             /* str2CreateAc=str2CreateAc + "ordinary_fee" + ordinary_fee;
            str2CreateAc=str2CreateAc + "express_fee" + express_fee;
            str2CreateAc=str2CreateAc + "readonly" + readonlys;
            str2CreateAc=str2CreateAc + "buyer_msg" + buyer_msg; */
            str2CreateAc = str2CreateAc  +   " seller "   +  sellerEmail;
             /* str2CreateAc=str2CreateAc + "buyer" + buyer;
            str2CreateAc=str2CreateAc + "buyer_name" + buyer_name;
            str2CreateAc=str2CreateAc + "buyer_address" + buyer_address;
            str2CreateAc=str2CreateAc + "buyer_zipcode" + buyer_zipcode;
            str2CreateAc=str2CreateAc + "buyer_tel" + buyer_tel;
            str2CreateAc=str2CreateAc + "buyer_mobile" + buyer_mobile; */
            str2CreateAc = str2CreateAc  +   " partner "   +  partner;
            str2CreateAc = str2CreateAc  +  keyCode;

             // acCode=FormsAuthentication.HashPasswordForStoringInConfigFile(str2CreateAc,"MD5");
            acCode = this .GetMD5(str2CreateAc, " gb2312 " );
            itemURL = INTERFACE_URL  +   " ?cmd= "   +  cmd;
            itemURL = itemURL  +   " &subject= "   +  HttpUtility.UrlEncode(subject);
            itemURL = itemURL  +   " &body= "   +  HttpUtility.UrlEncode(body);
            itemURL = itemURL  +   " &order_no= "   +  order_no;
            itemURL = itemURL  +   " &price= "   +  prices;
             // itemURL=itemURL + "&url=" + rurl;
            itemURL = itemURL  +   " &type= "   +  types;
            itemURL = itemURL  +   " &number= "   +  number;
            itemURL = itemURL  +   " &transport= "   +  transport;
             /* itemURL=itemURL + "&ordinary_fee=" + ordinary_fee;
            itemURL=itemURL + "&express_fee=" + express_fee;
            itemURL=itemURL + "&readonly=" + readonlys;
            itemURL=itemURL + "&buyer_msg=" + HttpUtility.UrlEncode(buyer_msg);
            itemURL=itemURL + "&buyer=" + HttpUtility.UrlEncode(buyer);
            itemURL=itemURL + "&buyer_name=" + HttpUtility.UrlEncode(buyer_name);
            itemURL=itemURL + "&buyer_address=" + HttpUtility.UrlEncode(buyer_address);
            itemURL=itemURL + "&buyer_zipcode=" + buyer_zipcode;
            itemURL=itemURL + "&buyer_tel=" + buyer_tel;
            itemURL=itemURL + "&buyer_mobile=" + buyer_mobile; */
            itemURL = itemURL  +   " &partner= "   +  partner;
            itemURL = itemURL  +   " &ac= "   +  acCode;
            AlipayItemURL = itemURL;
                         return  AlipayItemURL;
        }

这个函数就是返回生成的地址，里面注释掉的看你自己需要可以添加进去，然后就是md5码的问题，现在用默认的md5生成程序对中文的支持只限于GB2312，而支付宝使用的是GBK，虽然两个编码的内容GBK兼容GB2312但是毕竟两个编码方式不同，所以会产生错误，如果用英文或者数字不会有问题。上面下载里面带的一个md5.asp的算法支持中文。
        现在已经可以跳转到支付宝的页面了，而我们这边就要自己记录用户的信息已经生成的定单编号，这样在支付宝返回信息的时候来查询。在设定了返回地址后，我们就要看接收页面了。

string  msg_id,order_no,gross,buyer_email,buyer_name,buyer_address,buyer_zipcode,buyer_tel,buyer_mobile,action,s_date,ac,notify_type;
    
             string  returnTxt; // 返回给支付宝通知接口的结果
             string  alipayNotifyURL; // 支付宝查询接口URL
             string  myalipayEmail; // 商户的支付宝Email
             string  ResponseTxt = "" ;
    

            returnTxt             =   " N " ;
            alipayNotifyURL         =  ConfigurationSettings.AppSettings[ " interfaceback " ]; // 支付宝查询接口地址
            myalipayEmail         =  ConfigurationSettings.AppSettings[ " account " ]; // 填写您的支付宝帐号

    
             // 检查支付宝通知接口传递过来的参数是否合法
            msg_id             =  newop.DelStr(Request[ " msg_id " ]);
            order_no         =  newop.DelStr(Request[ " order_no " ]);
            gross             =  newop.DelStr(Request[ " gross " ]);
            buyer_email         =  newop.DelStr(Request[ " buyer_email " ]);
            buyer_name         =  newop.DelStr(Request[ " buyer_name " ]);
            buyer_address     =  newop.DelStr(Request[ " buyer_address " ]);
            buyer_zipcode     =  newop.DelStr(Request[ " buyer_zipcode " ]);
            buyer_tel         =  newop.DelStr(Request[ " buyer_tel " ]);
            buyer_mobile     =  newop.DelStr(Request[ " buyer_mobile " ]);
            action             =  newop.DelStr(Request[ " action " ]);
            s_date             =  newop.DelStr(Request[ " date " ]);
            ac                 =  newop.DelStr(Request[ " ac " ]);
            notify_type      =  newop.DelStr(Request[ " notify_type " ]);

            alipayNotifyURL     =  alipayNotifyURL  +   " msg_id= "   +  msg_id  +   " &email= "   +  myalipayEmail  +   " &order_no= "   +  order_no;
    
            System.Net.WebClient isClient =   new  System.Net.WebClient();
            Stream isStream  =  isClient.OpenRead(alipayNotifyURL);
            StreamReader isReader  =   new  StreamReader(isStream,System.Text.Encoding.GetEncoding( " GB2312 " ));
            ResponseTxt  =  isReader.ReadToEnd();

if (action  ==   " test " ) // 测试商户网站URL是否正确安装
            {
                returnTxt     =   " Y " ;
            }
             else   if ((action == " sendOff " ) && (msg_id != "" )) // 发货通知
            {
                returnTxt         =   " N " ;
                 if ((ResponseTxt  ==   " true " ) || (ResponseTxt  ==   " false " ))
                {
                     // 更新数据在商户系统里的订单数据；如果已经发货，则将returnTxt置为Y，否则为N
        
                }
                 else
                {
                     // 非法数据，不做更新
                    returnTxt = " Error " ;
                }
            }
             else   if ((action == " sendOff " ) && (notify_type == " web " ))
            {
                 // 检查是否已经付帐，并记录            }
             else   if ((action == " checkOut " ) && (msg_id != "" )) // 交易结束通知
            {
                returnTxt     =   " Y " ;
                 if ((ResponseTxt == " true " ) || (ResponseTxt  ==   " false " ))
                {
                     // 更新数据在商户系统里的订单数据；如果数据更新成功，则将returnTxt置为Y，否则为N
                     // 更新数据
                    
// 你的代码，更新你这边数据
                    returnTxt =   " Y " ;
                }
                 else
                {
                     // 非法数据，不做更新
                    returnTxt     =   " Error " ;
                }    
            }
             else
            {
                returnTxt = " Error " ;
            }
            Response.Write(returnTxt);

中间那段webclient是返回支付宝查询这个消息是不是支付宝发出的，这里也使用的是获取支付宝那里一个查询接口的结果，True或者False。
这样就完成了整个支付的流程，而你需要做的就是记录用户买的数据，然后接受支付宝给你的信息并确认是否正确，而且是否已经购买或者已经发货，从而完成你的销售过程。接收页面做的标准就是在直接访问的情况下显示的结果只有N或者Y或者其他你设定的returnTxt的值，如果有其他内容将会不能实现功能。
        支付宝现在的即时到帐功能还没有正式发布，请不要私自做，要不然会出现麻烦。