上传图文消息素材，获取图文消息的media_id：
/// <summary>
/// 请求Url，发送数据
/// </summary>
public static string PostUrl(string url, string postData)
{
byte[] data = Encoding.UTF8.GetBytes(postData);
// 设置参数
HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
CookieContainer cookieContainer = new CookieContainer();
request.CookieContainer = cookieContainer;
request.AllowAutoRedirect = true;
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = data.Length;
Stream outstream = request.GetRequestStream();
outstream.Write(data, 0, data.Length);
outstream.Close();
//发送请求并获取相应回应数据
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
//直到request.GetResponse()程序才开始向目标网页发送Post请求
Stream instream = response.GetResponseStream();
StreamReader sr = new StreamReader(instream, Encoding.UTF8);
//返回结果网页（html）代码
string content = sr.ReadToEnd();
return content;
}
/// <summary>
/// 上传图文消息素材返回media_id
/// </summary>
public static string UploadNews(string access_token, string postData)
{
return HttpRequestUtil.PostUrl(string.Format("https://www.easck.com/cgi-bin/media/uploadnews?access_token={0}", access_token), postData);
}
string articlesJson = ImgItemDal.GetArticlesJsonStr(this, access_token, dt);
string newsMsg = WXApi.UploadNews(access_token, articlesJson);
string newsid = Tools.GetJsonValue(newsMsg, "media_id");
4、群发图文消息
获取全部关注者OpenID集合(WXApi类)：
/// <summary>
/// 获取关注者OpenID集合
/// </summary>
public static List<string> GetOpenIDs(string access_token)
{
List<string> result = new List<string>();
List<string> openidList = GetOpenIDs(access_token, null);
result.AddRange(openidList);
while (openidList.Count > 0)
{
openidList = GetOpenIDs(access_token, openidList[openidList.Count - 1]);
result.AddRange(openidList);
}
return result;
}
/// <summary>
/// 获取关注者OpenID集合
/// </summary>
public static List<string> GetOpenIDs(string access_token, string next_openid)
{
// 设置参数
string url = string.Format("https://www.easck.com/cgi-bin/user/get?access_token={0}&next_openid={1}", access_token, string.IsNullOrWhiteSpace(next_openid) ? "" : next_openid);
string returnStr = HttpRequestUtil.RequestUrl(url);
int count = int.Parse(Tools.GetJsonValue(returnStr, "count"));
if (count > 0)
{
string startFlg = ""openid":[";
int start = returnStr.IndexOf(startFlg) + startFlg.Length;
int end = returnStr.IndexOf("]", start);
string openids = returnStr.Substring(start, end - start).Replace(""", "");
return openids.Split(',').ToList<string>();
}
else
{
return new List<string>();
}
}
