C#获取微信小程序的云数据库中数据的示例代码

{ "env":"小程序环境", "query": "db.collection(\"集合名称\").where({done:true}).limit(10).skip(1).get()" }

{ "env": "云环境ID", "file_list": [ { "fileid":"文件ID", "max_age":7200 } ] }

//需要添加的命名空间
using Newtonsoft.Json;
using System.IO;

/// <summary>
/// 发送http Get请求
/// </summary>
/// <param name="url"></param>
/// <returns></returns>
public static HttpWebResponse GetRequest(string url)
{
    HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
    request.Method = "GET";
    request.ContentType = "application/x-www-form-urlencoded";//链接类型
    return request.GetResponse() as HttpWebResponse;
}

/// <summary>
/// 发送http Post请求
/// </summary>
/// <returns></returns>
public static HttpWebResponse PostRequest(string url, string messsage)
{
    byte[] byteData = Encoding.UTF8.GetBytes(messsage);
    HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(url);
    webRequest.Method = "POST";
    webRequest.ContentType = "application/json;charset=UTF-8";
    webRequest.ContentLength = byteData.Length;
    using (Stream stream = webRequest.GetRequestStream())
    {
        stream.Write(byteData, 0, byteData.Length);
    }
    HttpWebResponse response = (HttpWebResponse)webRequest.GetResponse();
    return response;
}

/// <summary>
/// 从HttpWebResponse对象中提取响应的数据转换为字符串
/// </summary>
/// <param name="webresponse"></param>
/// <returns></returns>
public static string HttpWebResponseToString(HttpWebResponse webresponse)
{
    using (Stream s = webresponse.GetResponseStream())
    {
        StreamReader reader = new StreamReader(s, Encoding.UTF8);
        return reader.ReadToEnd();
    }
}

/// <summary>
/// Json字符串转为匿名对象
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="json"></param>
/// <param name="anonymousTypeObject"></param>
/// <returns></returns>
public static T DesAnonymousType<T>(string json, T anonymousTypeObject)
{
    return JsonConvert.DeserializeAnonymousType(json, anonymousTypeObject);
}

/// <summary>
/// 获取access_token
/// </summary>
/// <returns></returns>
public static string GetAccessToken()
{
    // 通过Get请求获取access_token
    HttpWebResponse httpWebResponse = GetRequest("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credentiaappid=小程序ID&secret=小程序密钥");
    string resultJson = HttpWebResponseToString(httpWebResponse);
    var resultObj = DesAnonymousType(resultJson, new { access_token = "", expires_in = "" });
    return resultObj.access_token;
}

/// <summary>
///  查询数据
/// </summary>
/// <param name="queryString">形如： $"{{\"env\":\"小程序环境id\", \"query\": \"db.collecti(\\\"数据集合名称\\\").where({{集合中字段:\\\"集合中字段值\\\"}}).limit(10).get()\"}}"</param>
/// <returns></returns>
public static string GetData(string queryString)
{
    string accessToken = GetAccessToken();
    HttpWebResponse httpWebResponse = PostRequest("https://api.weixin.qq.com/tcb/databasequery?access_token=" + accessTokenqueryString);
    string data = HttpWebResponseToString(httpWebResponse);
    return data;
}


/// <summary>
/// 通过FileId获取文件下载URL
/// </summary>
/// <param name="queryString">形如：$"{{\"env\": \"环境ID\",\"file_list\": [{{\"fileid\":文件ID\",\"max_age\":7200 }}]}}"</param>
/// <returns></returns>
public static string GetDownFileUrl(string queryString)
{
    string accessToken = GetAccessToken();
    string url = $"https://api.weixin.qq.com/tcb/batchdownloadfile?access_token={accessToken}";
    HttpWebResponse httpWebResponse = PostRequest(url, queryString);
    string downFileUrl = HttpWebResponseToString(httpWebResponse);
    return downFileUrl;
}