1. string result = HttpGet("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=wx***********d&secret=a*******************4");
2. public static string HttpGet(string Url)
3. {
4. HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
5. request.Method = "GET";
6. request.ContentType = "text/html;charset=UTF-8";
7.  
8.  
9. HttpWebResponse response = (HttpWebResponse)request.GetResponse();
10. Stream myResponseStream = response.GetResponseStream();
11. StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.UTF8);
12. string retString = myStreamReader.ReadToEnd();
13. myStreamReader.Close();
14. myResponseStream.Close();
15.  
16.  
17.  
18. return retString;
19. }

其中****改成自己的。具體到微信公眾平臺小程序里設置開發設置里找。

第二步 獲取推廣二維碼

文檔：

參數 默認值 說明  path 不能為空，最大長度 128 字節  width 430 二維碼的寬度 代碼：

1. public static void PostMoths(string access_token)
2. {
3. string _url = "https://api.weixin.qq.com/cgi-bin/wxaapp/createwxaqrcode?access_token=" + access_token;
4.  
5.  
6. string strURL = _url;
7. System.NET.HttpWebRequest request;
8. request = (System.Net.HttpWebRequest)WebRequest.Create(strURL);
9. request.Method = "POST";
10. request.ContentType = "application/json;charset=UTF-8";
11. JsonData _data = new JsonData();
12. _data["path"] = "pages/index?query=1";
13. _data["width"] = "430";
14.  
15.  
16. string _jso = _data.ToJson();
17. //string paraUrlCoded = param;
18. byte[] payload;
19. //payload = System.Text.Encoding.UTF8.GetBytes(paraUrlCoded);
20. payload = System.Text.Encoding.UTF8.GetBytes(_jso);
21. request.ContentLength = payload.Length;
22. Stream writer = request.GetRequestStream();
23. writer.Write(payload, 0, payload.Length);
24. writer.Close();
25. System.Net.HttpWebResponse response;
26. response = (System.Net.HttpWebResponse)request.GetResponse();
27. System.IO.Stream s;
28. s = response.GetResponseStream();
29. string StrDate = "";
30. string strValue = "";
31. byte[] tt = StreamToBytes(s);
32. //將流保存在c盤test.png文件下
33. System.IO.File.WriteAllBytes(@"d:\test.png", tt);
34. }
35. ///將數據流轉為byte[]
36. public static byte[] StreamToBytes(Stream stream)
37. {
38. List<byte> bytes = new List<byte>();
39. int temp = stream.ReadByte();
40. while (temp != -1)
41. {
42. bytes.Add((byte)temp);
43. temp = stream.ReadByte();
44. }
45. return bytes.ToArray();
46. }

最后保存在d盤的圖片就是推廣二維碼，可以講服務器連接地址發給微信小程序，供微信小程序調用。