crm.core/code/Crm.Core.Common/Helpers/AliHelper.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.Web;

namespace Crm.Core.Common.Helpers
{

    public class AliHelper
    {
        private string AccessKeyId = ""; //密钥ID
        private string AccessKeySecret = "";
        private string Format = "JSON"; //返回值的类型
        private string Version = ""; //API版本号
        private string Signature = ""; //签名结果串
        private string SignatureMethod = "HMAC-SHA1"; //签名方式，目前支持HMAC-SHA1
        private string Timestamp = DateTime.UtcNow.ToString("yyyy-MM-ddTHH:mm:ssZ"); //请求的时间戳 日期格式按照ISO8601标准表示，并需要使用UTC时间 yyyy-MM-ddTHH:mm:ssZ;
        private string SignatureVersion = "1.0"; //签名算法版本
        private string SignatureNonce = Guid.NewGuid().ToString(); //唯一随机数，用于防止网络重放攻击。用户在不同请求间要使用不同的随机数值

        public AliHelper(string AccessKeyId, string AccessKeySecret, string Version)
        {
            this.AccessKeyId = AccessKeyId;
            this.AccessKeySecret = AccessKeySecret;
            this.Version = Version;
        }

        /// <summary>
        /// 计算签名
        /// </summary>
        /// 

        private void ComputeSignature(Dictionary<string, object> ditParam, string method = "GET")
        {
            BuildParameters(ditParam);

            //按ascii码排序   
            Dictionary<string, object> asciiDit = new Dictionary<string, object>();
            string[] KeyArr = ditParam.Keys.ToArray();
            Array.Sort(KeyArr, string.CompareOrdinal);
            foreach (var key in KeyArr)
            {
                string value = ditParam[key].ToString();
                asciiDit.Add(key, value);
            }


            //计算签名    
            var canonicalizedQueryString = string.Join("&",
                asciiDit.Select(x => PercentEncode(x.Key) + "=" + PercentEncode(x.Value.ToString())));

            var stringToSign = method.ToString().ToUpper() + "&" + PercentEncode("/") + "&" + PercentEncode(canonicalizedQueryString);
            var keyBytes = Encoding.UTF8.GetBytes(AccessKeySecret + "&");
            var hmac = new HMACSHA1(keyBytes);
            var hashBytes = hmac.ComputeHash(Encoding.UTF8.GetBytes(stringToSign));
            Signature = Convert.ToBase64String(hashBytes);


            ditParam.Add("Signature", Signature);
        }




        //获取公共参数和相关方法中的参数
        private void BuildParameters(Dictionary<string, object> ditParam)
        {
            ditParam.Add("Format", Format.ToUpper());
            ditParam.Add("Version", Version);
            ditParam.Add("AccessKeyId", AccessKeyId);
            ditParam.Add("Timestamp", Timestamp);
            ditParam.Add("SignatureMethod", SignatureMethod);
            ditParam.Add("SignatureVersion", SignatureVersion);
            ditParam.Add("SignatureNonce", SignatureNonce);
        }


        private string PercentEncode(string value)
        {
            return UpperCaseUrlEncode(value)
                .Replace("/", "%2F")
                .Replace("+", "%20")
                .Replace("*", "%2A")
                .Replace("%7E", "~")
                .Replace("!", "%21")
                .Replace("'", "%27")
                .Replace("(", "%28")
                .Replace(")", "%29");
        }

        private string UpperCaseUrlEncode(string s)
        {
            // C# 的 HttpUtility.UrlEncode() 编码得到的形如 %xx%xx的内容是小写的，Java 的是大写的。
            char[] temp = HttpUtility.UrlEncode(s).ToCharArray();
            for (int i = 0; i < temp.Length - 2; i++)
            {
                if (temp[i] == '%')
                {
                    temp[i + 1] = char.ToUpper(temp[i + 1]);
                    temp[i + 2] = char.ToUpper(temp[i + 2]);
                }
            }
            return new string(temp);
        }


        public string HttpGetUrl(string Url, Dictionary<string, object> ditParam)
        {
            ComputeSignature(ditParam);
            var param = string.Join("&", ditParam.Select(x => x.Key + "=" + HttpUtility.UrlEncode(x.Value.ToString())));

            var u = Url + (param == "" ? "" : "?") + param;

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(u);
            request.Method = "GET";
            request.ContentType = "text/html;charset=UTF-8";
            HttpWebResponse response;
            try
            {
                response = (HttpWebResponse)request.GetResponse();

            }
            catch (WebException ex)
            {
                response = (HttpWebResponse)ex.Response;
            }

            Stream myResponseStream = response.GetResponseStream();
            StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));
            string retString = myStreamReader.ReadToEnd();
            myStreamReader.Close();
            myResponseStream.Close();
            return retString;
        }


    }
    public class Credentials
    {
        public string SecurityToken { get; set; }
        public string AccessKeyId { get; set; }
        public string AccessKeySecret { get; set; }
        public string Expiration { get; set; }
    }
}