微信公众平台开发教程（六）获取个性二维码的实例

http请求方式: POST
URL: https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token=TOKEN
POST数据格式：json
POST数据例子：{"expire_seconds": 1800, "action_name": "QR_SCENE", "action_info": {"scene": {"scene_id": 123}}}

http请求方式: POST
URL: https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token=TOKEN
POST数据格式：json
POST数据例子：{"action_name": "QR_LIMIT_SCENE", "action_info": {"scene": {"scene_id": 123}}}

Accept-Ranges:bytes
Cache-control:max-age=604800
Connection:keep-alive
Content-Length:28026
Content-Type:image/jpg
Date:Wed, 16 Oct 2013 06:37:10 GMT
Expires:Wed, 23 Oct 2013 14:37:10 +0800
Server:nginx/1.4.1

/// <summary>
 /// 二维码管理者
 /// </summary>
 public class DimensionalCodeManager
 {
 /// <summary>
 /// 临时二维码地址
 /// </summary>
 /// 使用string.format时，报：字符串格式错误，因为其中有{
 //private const string TEMP_URL = "{\"expire_seconds\": 1800, \"action_name\": \"QR_SCENE\", \"action_info\": {\"scene\": {\"scene_id\": {0}}}}";
 /// <summary>
 /// 解决办法，将原有字符串中的一个{用两个{代替
 /// </summary>
 private const string TEMP_JSON_DATA = "{{\"expire_seconds\": 1800, \"action_name\": \"QR_SCENE\", \"action_info\": {{\"scene\": {{\"scene_id\": {0}}}}}}}";
 /// <summary>
 /// 永久二维码地址
 /// </summary>
 private const string PERMANENT_URL = "{{\"action_name\": \"QR_LIMIT_SCENE\", \"action_info\": {{\"scene\": {{\"scene_id\": {0}}}}}}}";
 /// <summary>
 /// 获取ticket的URL
 /// </summary>
 private const string GET_TICKET_URL = " https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token={0}";
 /// <summary>
 /// 获取二维码URL
 /// </summary>
 private const string GET_CODE_URL = "https://mp.weixin.qq.com/cgi-bin/showqrcode?ticket={0}";
 /// <summary>
 /// 根据场景ID获取ticket
 /// </summary>
 /// <param name="sceneID">场景ID</param>
 /// <param name="isTemp">是否是临时二维码</param>
 /// <returns></returns>
 private static string GetTicket(int sceneID, bool isTemp)
 {
  string result = null;
  string data = string.Empty;
  if (isTemp)
  {
  data = string.Format(TEMP_JSON_DATA, sceneID.ToString());
  }
  else
  {
  if (sceneID > 0 && sceneID <= 1000)
  {
   data = string.Format(PERMANENT_URL, sceneID);
  }
  else
  {
   //scene_id不合法
   return null;
  }
  }

  string ticketJson = HttpUtility.GetData(string.Format(GET_TICKET_URL,Context.AccessToken));

  XDocument doc = XmlUtility.ParseJson(ticketJson, "root");
  XElement root = doc.Root;
  if (root != null)
  {
  XElement ticket = root.Element("ticket");
  if (ticket != null)
  {
   result = ticket.Value;
  }
  }

  return result;
 }
 /// <summary>
 /// 创建临时二维码
 /// </summary>
 /// <param name="sceneID">场景id，int类型</param>
 /// <returns></returns>
 public static string GenerateTemp(int sceneID)
 {
  string ticket = GetTicket(sceneID,true);
  if (ticket == null)
  {
  return null;
  }

  return HttpUtility.GetData(string.Format(GET_CODE_URL, ticket));
 }
 /// <summary>
 /// 创建临时二维码
 /// </summary>
 /// <param name="sceneID">场景id，int类型</param>
 /// <returns></returns>
 public static string GeneratePermanent(int sceneID)
 {
  string ticket = GetTicket(sceneID, false);
  if (ticket == null)
  {
  return null;
  }

  return HttpUtility.GetData(string.Format(GET_CODE_URL, ticket));
 }
 }