c# 静态类的使用场景

public class fnComm
  {    
    public static JObject Post(HttpClient myhttp, string url, JObject json)
    {
      HttpContent content = new StringContent(JsonConvert.SerializeObject(json), Encoding.UTF8, "application/json");
      var message = Task<HttpResponseMessage>.Run<HttpResponseMessage>(() =>
      {
        return myhttp.PostAsync(url, content);
      });
      message.Wait();
      //接收返回得信息
      if (message.Result.IsSuccessStatusCode)
      {
        var s = Task.Run(() =>
        {
          return message.Result.Content.ReadAsStringAsync();
        });
        s.Wait();
        return JObject.Parse(s.Result);
      }
      else
      {
        throw new Exception("StatusCode:" + message.Result.StatusCode.ToString());
      }
    }
    public static byte[] ConvertToByteAry(object obj)
    {
      var j = JsonConvert.SerializeObject(obj);
      var ary = System.Text.Encoding.UTF8.GetBytes(j);
      return ary;
    }

    /// <summary>
    /// datetime转换为unixtime
    /// </summary>
    /// <param name="time"></param>
    /// <returns></returns>
    public static int TimeToUnixTime(System.DateTime time)
    {
      return (int)(time - new DateTime(1970, 1, 1).ToLocalTime()).TotalSeconds;
    }

    public static string GenerateTransId(int i)
    {
      string transId = DateTime.Now.ToString("yyyyMMddHHmmss");
      int l = i - 14;
      return transId + CreateRandCode(l);

    }

    public static string CreateRandCode(int codeLen)
    {
      string codeSerial = "1,2,3,4,5,6,7,a,c,d,e,f,h,i,j,k,m,n,p,r,s,t,A,C,D,E,F,G,H,J,K,M,N,P,Q,R,S,U,V,W,X,Y,Z";
      if (codeLen == 0)
      {
        codeLen = 16;
      }
      string[] arr = codeSerial.Split(',');
      string code = "";
      int randValue = -1;
      Random rand = new Random(unchecked((int)DateTime.Now.Ticks));
      for (int i = 0; i < codeLen; i++)
      {
        randValue = rand.Next(0, arr.Length - 1);
        code += arr[randValue];
      }
      return code;
    }

    public static string GetStringFromList(List<string> list)
    {
      StringBuilder sb = new StringBuilder();
      string strReturn;
      if (list.Count > 0)
      {
        foreach (string item in list)
        {
          sb.AppendFormat("'{0}',", item);
        }
        strReturn = sb.ToString(0, sb.Length - 1);
      }
      else
      {
        strReturn = "''";
      }
      return strReturn;
    }
  }