/// <summary>
/// 微信公众平台操作类
/// </summary>
public class weixin
{
private string Token = "my_weixin_token"; //换成自己的token
public void Auth()
{
string echoStr = System.Web.HttpContext.Current.Request.QueryString["echoStr"];
if (CheckSignature()) //校验签名是否正确
{
if (!string.IsNullOrEmpty(echoStr))
{
System.Web.HttpContext.Current.Response.Write(echoStr); //返回原值表示校验成功
System.Web.HttpContext.Current.Response.End();
}
}
}


public void Handle(string postStr)
{
//封装请求类
XmlDocument doc = new XmlDocument();
doc.LoadXml(postStr);
XmlElement rootElement = doc.DocumentElement;
//MsgType
XmlNode MsgType = rootElement.SelectSingleNode("MsgType");
//接收的值--->接收消息类(也称为消息推送)
RequestXML requestXML = new RequestXML();
requestXML.ToUserName = rootElement.SelectSingleNode("ToUserName").InnerText;
requestXML.FromUserName = rootElement.SelectSingleNode("FromUserName").InnerText;
requestXML.CreateTime = rootElement.SelectSingleNode("CreateTime").InnerText;
requestXML.MsgType = MsgType.InnerText;

//根据不同的类型进行不同的处理
switch (requestXML.MsgType)
{
case "text": //文本消息
requestXML.Content = rootElement.SelectSingleNode("Content").InnerText;
break;
case "image": //图片
requestXML.PicUrl = rootElement.SelectSingleNode("PicUrl").InnerText;
break;
case "location": //位置
requestXML.Location_X = rootElement.SelectSingleNode("Location_X").InnerText;
requestXML.Location_Y = rootElement.SelectSingleNode("Location_Y").InnerText;
requestXML.Scale = rootElement.SelectSingleNode("Scale").InnerText;
requestXML.Label = rootElement.SelectSingleNode("Label").InnerText;
break;
case "link": //链接
break;
case "event": //事件推送 支持V4.5+
break;
}

//消息回复
ResponseMsg(requestXML);
}


/// <summary>
/// 验证微信签名
/// * 将token、timestamp、nonce三个参数进行字典序排序
/// * 将三个参数字符串拼接成一个字符串进行sha1加密
/// * 开发者获得加密后的字符串可与signature对比，标识该请求来源于微信。
/// </summary>
/// <returns></returns>
private bool CheckSignature()
{
string signature = System.Web.HttpContext.Current.Request.QueryString["signature"];
string timestamp = System.Web.HttpContext.Current.Request.QueryString["timestamp"];
string nonce = System.Web.HttpContext.Current.Request.QueryString["nonce"];
//加密/校验流程：
//1. 将token、timestamp、nonce三个参数进行字典序排序
string[] ArrTmp = { Token, timestamp, nonce }; 
Array.Sort(ArrTmp);//字典排序
//2.将三个参数字符串拼接成一个字符串进行sha1加密
string tmpStr = string.Join("", ArrTmp);
tmpStr = FormsAuthentication.HashPasswordForStoringInConfigFile(tmpStr, "SHA1");
tmpStr = tmpStr.ToLower();
//3.开发者获得加密后的字符串可与signature对比，标识该请求来源于微信。
if (tmpStr == signature)
{
return true;
}
else
{
return false;
}
}

/// <summary>
/// 消息回复(微信信息返回)
/// </summary>
/// <param name="requestXML">The request XML.</param>
private void ResponseMsg(RequestXML requestXML)
{
try
{
string resxml = "";
//主要是调用数据库进行关键词匹配自动回复内容，可以根据自己的业务情况编写。
//1.通常有，没有匹配任何指令时，返回帮助信息
AutoResponse mi = new AutoResponse(requestXML.Content, requestXML.FromUserName);

switch (requestXML.MsgType)
{
case "text":
//在这里执行一系列操作，从而实现自动回复内容. 
string _reMsg = mi.GetReMsg();
if (mi.msgType == 1)
{
resxml = "<xml><ToUserName><![CDATA[" + requestXML.FromUserName + "]]></ToUserName><FromUserName><![CDATA[" + requestXML.ToUserName + "]]></FromUserName><CreateTime>" + ConvertDateTimeInt(DateTime.Now) + "</CreateTime><MsgType><![CDATA[news]]></MsgType><Content><![CDATA[]]></Content><ArticleCount>2</ArticleCount><Articles>";
resxml += mi.GetRePic(requestXML.FromUserName);
resxml += "</Articles><FuncFlag>1</FuncFlag></xml>";
}
else
{
resxml = "<xml><ToUserName><![CDATA[" + requestXML.FromUserName + "]]></ToUserName><FromUserName><![CDATA[" + requestXML.ToUserName + "]]></FromUserName><CreateTime>" + ConvertDateTimeInt(DateTime.Now) + "</CreateTime><MsgType><![CDATA[text]]></MsgType><Content><![CDATA[" + _reMsg + "]]></Content><FuncFlag>1</FuncFlag></xml>";
}
break;
case "location":
string city = GetMapInfo(requestXML.Location_X, requestXML.Location_Y);
if (city == "0")
{
resxml = "<xml><ToUserName><![CDATA[" + requestXML.FromUserName + "]]></ToUserName><FromUserName><![CDATA[" + requestXML.ToUserName + "]]></FromUserName><CreateTime>" + ConvertDateTimeInt(DateTime.Now) + "</CreateTime><MsgType><![CDATA[text]]></MsgType><Content><![CDATA[好啦，我们知道您的位置啦。您可以:" + mi.GetDefault() + "]]></Content><FuncFlag>1</FuncFlag></xml>";
}
else
{
resxml = "<xml><ToUserName><![CDATA[" + requestXML.FromUserName + "]]></ToUserName><FromUserName><![CDATA[" + requestXML.ToUserName + "]]></FromUserName><CreateTime>" + ConvertDateTimeInt(DateTime.Now) + "</CreateTime><MsgType><![CDATA[text]]></MsgType><Content><![CDATA[好啦，我们知道您的位置啦。您可以:" + mi.GetDefault() + "]]></Content><FuncFlag>1</FuncFlag></xml>";
}
break;
case "image":
//图文混合的消息 具体格式请见官方API“回复图文消息” 
break;
}

System.Web.HttpContext.Current.Response.Write(resxml);
WriteToDB(requestXML, resxml, mi.pid);
}
catch (Exception ex)
{
//WriteTxt("异常：" + ex.Message + "Struck:" + ex.StackTrace.ToString());
//wx_logs.MyInsert("异常：" + ex.Message + "Struck:" + ex.StackTrace.ToString());
}
}


/// <summary>
/// unix时间转换为datetime
/// </summary>
/// <param name="timeStamp"></param>
/// <returns></returns>
private DateTime UnixTimeToTime(string timeStamp)
{
DateTime dtStart = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
long lTime = long.Parse(timeStamp + "0000000");
TimeSpan toNow = new TimeSpan(lTime);
return dtStart.Add(toNow);
}


/// <summary>
/// datetime转换为unixtime
/// </summary>
/// <param name="time"></param>
/// <returns></returns>
private int ConvertDateTimeInt(System.DateTime time)
{
System.DateTime startTime = TimeZone.CurrentTimeZone.ToLocalTime(new System.DateTime(1970, 1, 1));
return (int)(time - startTime).TotalSeconds;
}


/// <summary>
/// 调用百度地图，返回坐标信息
/// </summary>
/// <param name="y">经度</param>
/// <param name="x">纬度</param>
/// <returns></returns>
public string GetMapInfo(string x, string y)
{
try
{
string res = string.Empty;
string parame = string.Empty;
string url = "http://maps.googleapis.com/maps/api/geocode/xml";

parame = "latlng=" + x + "," + y + "&language=zh-CN&sensor=false";//此key为个人申请
res = webRequestPost(url, parame);

XmlDocument doc = new XmlDocument();
doc.LoadXml(res);

XmlElement rootElement = doc.DocumentElement;
string Status = rootElement.SelectSingleNode("status").InnerText;

if (Status == "OK")
{
//仅获取城市
XmlNodeList xmlResults = rootElement.SelectSingleNode("/GeocodeResponse").ChildNodes;
for (int i = 0; i < xmlResults.Count; i++)
{
XmlNode childNode = xmlResults[i];
if (childNode.Name == "status") {
continue;
}
string city = "0";
for (int w = 0; w < childNode.ChildNodes.Count; w++)
{
for (int q = 0; q < childNode.ChildNodes[w].ChildNodes.Count; q++)
{
XmlNode childeTwo = childNode.ChildNodes[w].ChildNodes[q];
if (childeTwo.Name == "long_name")
{
city = childeTwo.InnerText;
}
else if (childeTwo.InnerText == "locality")
{
return city;
}
}
}
return city;
}
}
}
catch (Exception ex)
{
//WriteTxt("map异常:" + ex.Message.ToString() + "Struck:" + ex.StackTrace.ToString());
return "0";
} 
return "0";
}


/// <summary>
/// Post 提交调用抓取
/// </summary>
/// <param name="url">提交地址</param>
/// <param name="param">参数</param>
/// <returns>string</returns>
public string webRequestPost(string url, string param)
{
byte[] bs = System.Text.Encoding.UTF8.GetBytes(param);
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url + "?" + param);
req.Method = "Post";
req.Timeout = 120 * 1000;
req.ContentType = "application/x-www-form-urlencoded;";
req.ContentLength = bs.Length;

using (Stream reqStream = req.GetRequestStream())
{
reqStream.Write(bs, 0, bs.Length);
reqStream.Flush();
}

using (WebResponse wr = req.GetResponse())
{
//在这里对接收到的页面内容进行处理
Stream strm = wr.GetResponseStream();
StreamReader sr = new StreamReader(strm, System.Text.Encoding.UTF8);

string line;
System.Text.StringBuilder sb = new System.Text.StringBuilder();
while ((line = sr.ReadLine()) != null)
{
sb.Append(line + System.Environment.NewLine);
}
sr.Close();
strm.Close();
return sb.ToString();
}
}

/// <summary>
/// 将本次交互信息保存至数据库中
/// </summary>
/// <param name="requestXML"></param>
/// <param name="_xml"></param>
/// <param name="_pid"></param>
private void WriteToDB(RequestXML requestXML, string _xml, int _pid)
{
WeiXinMsg wx = new WeiXinMsg();
wx.FromUserName = requestXML.FromUserName;
wx.ToUserName = requestXML.ToUserName;
wx.MsgType = requestXML.MsgType;
wx.Msg = requestXML.Content;
wx.Creatime = requestXML.CreateTime;
wx.Location_X = requestXML.Location_X;
wx.Location_Y = requestXML.Location_Y;
wx.Label = requestXML.Label;
wx.Scale = requestXML.Scale;
wx.PicUrl = requestXML.PicUrl;
wx.reply = _xml;
wx.pid = _pid;
try
{
wx.Add();
}
catch (Exception ex)
{
//wx_logs.MyInsert(ex.Message);
//ex.message;
}
}
}