微信公眾平臺開發(fā)之處理圖片.Net代碼解析

/// <summary>
 /// 下載保存多媒體文件,返回多媒體保存路徑
 /// </summary>
 /// <param name="ACCESS_TOKEN"></param>
 /// <param name="MEDIA_ID"></param>
 /// <returns></returns>
 public string GetMultimedia(string ACCESS_TOKEN, string MEDIA_ID)
 {
 string file = string.Empty;
 string content = string.Empty;
 string strpath = string.Empty;
 string savepath = string.Empty;
 string stUrl = "http://file.api.weixin.qq.com/cgi-bin/media/get?access_token=" + ACCESS_TOKEN + "&media_id=" + MEDIA_ID;

 HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(stUrl);

 req.Method = "GET";
 using (WebResponse wr = req.GetResponse())
 {
 HttpWebResponse myResponse = (HttpWebResponse)req.GetResponse();

 strpath = myResponse.ResponseUri.ToString();
 WriteLog("接收類別://" + myResponse.ContentType);
 WebClient mywebclient = new WebClient();
 savepath = Server.MapPath("image") + "\\" + DateTime.Now.ToString("yyyyMMddHHmmssfff") + (new Random()).Next().ToString().Substring(0, 4) + ".jpg";
 WriteLog("路徑://" + savepath);
 try
 {
 mywebclient.DownloadFile(strpath, savepath);
 file = savepath;
 }
 catch (Exception ex)
 {
 savepath = ex.ToString();
 }

 }
 return file;
 }

 class wxmessage 
 { 
 public string FromUserName { get; set; } 
 public string ToUserName { get; set; } 
 public string MsgType { get; set; } 
 public string EventName { get; set; } 
 public string Content { get; set; }
 public string Recognition { get; set; }
 public string MediaId { get; set; }
 public string EventKey { get; set; } 
 }

private wxmessage GetWxMessage()
 {
 wxmessage wx = new wxmessage();
 StreamReader str = new StreamReader(Request.InputStream, System.Text.Encoding.UTF8);
 XmlDocument xml = new XmlDocument();
 xml.Load(str);
 wx.ToUserName = xml.SelectSingleNode("xml").SelectSingleNode("ToUserName").InnerText;
 wx.FromUserName = xml.SelectSingleNode("xml").SelectSingleNode("FromUserName").InnerText;
 wx.MsgType = xml.SelectSingleNode("xml").SelectSingleNode("MsgType").InnerText;
 if (wx.MsgType.Trim() == "text")
 {
 wx.Content = xml.SelectSingleNode("xml").SelectSingleNode("Content").InnerText;
 }
 if (wx.MsgType.Trim() == "event")
 {
 wx.EventName = xml.SelectSingleNode("xml").SelectSingleNode("Event").InnerText;
 wx.EventKey = xml.SelectSingleNode("xml").SelectSingleNode("EventKey").InnerText;
 }
 if (wx.MsgType.Trim() == "voice")
 {
 wx.Recognition = xml.SelectSingleNode("xml").SelectSingleNode("Recognition").InnerText;
 }
 if (wx.MsgType.Trim() == "image")
 {
 wx.MediaId = xml.SelectSingleNode("xml").SelectSingleNode("MediaId").InnerText;
 }
 
 return wx;
 }

/// <summary>
 /// 上傳多媒體文件,返回 MediaId
 /// </summary>
 /// <param name="ACCESS_TOKEN"></param>
 /// <param name="Type"></param>
 /// <returns></returns>
 public string UploadMultimedia(string ACCESS_TOKEN, string Type)
 {
 string result = "";
 string wxurl = "http://file.api.weixin.qq.com/cgi-bin/media/upload?access_token=" + ACCESS_TOKEN + "&type=" + Type;
 string filepath = Server.MapPath("image") + "\\hemeng80.jpg";(本地服務器的地址)
 WriteLog("上傳路徑:" + filepath);
 WebClient myWebClient = new WebClient();
 myWebClient.Credentials = CredentialCache.DefaultCredentials;
 try
 {
 byte[] responseArray = myWebClient.UploadFile(wxurl, "POST", filepath);
 result = System.Text.Encoding.Default.GetString(responseArray, 0, responseArray.Length);
 WriteLog("上傳result:" + result);
 UploadMM _mode = JsonHelper.ParseFromJson<UploadMM>(result);
 result = _mode.media_id;
 }
 catch (Exception ex)
 {
 result = "Error:" + ex.Message;
 }
 WriteLog("上傳MediaId:" + result);
 return result;
 }

protected string sendPicTextMessage(Msg _mode, string MediaId)
 {
 string res = string.Format(@"<xml>
 <ToUserName><![CDATA[{0}]]></ToUserName>
 <FromUserName><![CDATA[{1}]]></FromUserName>
 <CreateTime>{2}</CreateTime>
 <MsgType><![CDATA[image]]></MsgType>
 <Image>
 <MediaId><![CDATA[{3}]]></MediaId>
 </Image>
 </xml> ",
 _mode.FromUserName, _mode.ToUserName, DateTime.Now, MediaId);

 return res;
 }