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CSharp · Console

/Program.cs

using System;
using System.Security.Cryptography;
using System.Text;
using System.Linq;
					
public class Program
{
	public static byte[] GetKey(string siteSecret)
    {
        byte[] key = Encoding.UTF8.GetBytes(siteSecret);
        return SHA1.Create().ComputeHash(key).Take(16).ToArray();
    }

    public static string EncryptAes(string input, string siteSecret)
    {
        var key = GetKey(siteSecret);
        using (var aes = AesManaged.Create())
        {
            if (aes == null) return null;

            aes.Mode = CipherMode.ECB;
            aes.Padding = PaddingMode.PKCS7;
            aes.Key = key;
            byte[] inputBytes = Encoding.UTF8.GetBytes(input);

            var enc = aes.CreateEncryptor(key, new byte[16]);
            return UrlSafeBase64(enc.TransformFinalBlock(inputBytes,0,input.Length));
        }
    }

    // http://stackoverflow.com/a/26354677/162671
    public static string UrlSafeBase64(byte[] bytes)
    {
        return Convert.ToBase64String(bytes).TrimEnd('=')
            .Replace('+', '-')
            .Replace('/', '_');
    }
	
    public static void Main(string[] args)
    {
        string siteSecret = "12345678";
        string jsonToken = "{'session_id':'abf52ca5-9d87-4061-b109-334abb7e637a','ts_ms':1445705791480}";

        Console.WriteLine(" json token: " + jsonToken);
        Console.WriteLine(" siteSecret: " + siteSecret);
        Console.WriteLine(EncryptAes(jsonToken, siteSecret));
        Console.ReadLine();
    }
}