如何为here接口c#生成签名

using System;
using System.Security.Cryptography;
using System.Text;

public class HereSignatureGenerator
{
    public static string GenerateSignature(string apiKey, string apiSecret, string requestParams)
    {
        // 将请求参数按照字母顺序进行排序
        var sortedParams = SortParams(requestParams);

        // 将排序后的参数按照key=value的格式拼接成一个字符串
        var paramString = BuildParamString(sortedParams);

        // 将拼接好的字符串与密钥进行拼接
        var signString = paramString + apiSecret;

        // 使用哈希算法对拼接后的字符串进行加密，生成签名
        var signature = ComputeHash(signString);

        return signature;
    }

    private static SortedDictionary<string, string> SortParams(string requestParams)
    {
        // 将请求参数按照字母顺序进行排序
        var sortedParams = new SortedDictionary<string, string>();

        // 解析请求参数，将其存储到sortedParams字典中
        // 这里假设requestParams是一个以&分隔的参数字符串，如key1=value1&key2=value2
        var paramArray = requestParams.Split('&');
        foreach (var param in paramArray)
        {
            var keyValue = param.Split('=');
            var key = keyValue[0];
            var value = keyValue[1];
            sortedParams.Add(key, value);
        }

        return sortedParams;
    }

    private static string BuildParamString(SortedDictionary<string, string> sortedParams)
    {
        // 将排序后的参数按照key=value的格式拼接成一个字符串
        var paramString = new StringBuilder();
        foreach (var param in sortedParams)
        {
            paramString.Append(param.Key).Append("=").Append(param.Value).Append("&");
        }

        // 去除末尾的&
        paramString.Length--;

        return paramString.ToString();
    }

    private static string ComputeHash(string input)
    {
        // 使用哈希算法对字符串进行加密，生成签名
        using (var algorithm = MD5.Create())
        {
            var hashBytes = algorithm.ComputeHash(Encoding.UTF8.GetBytes(input));
            var signature = BitConverter.ToString(hashBytes).Replace("-", "").ToLower();
            return signature;
        }
    }
}

var apiKey = "your_api_key";
var apiSecret = "your_api_secret";
var requestParams = "param1=value1&param2=value2";

var signature = HereSignatureGenerator.GenerateSignature(apiKey, apiSecret, requestParams);
Console.WriteLine("Generated Signature: " + signature);