c#随机生成IP地址

 public static string ipsite()
        {
            Random sj = new Random();
            var s = "";
            for (int i = 0; i <= 3; i++)
            {
                var q = sj.Next(0, 255).ToString();
                if (i<3)
                {
                    s += (q + ".").ToString();
                }
                else
                {
                    s += q.ToString();
                }              
            }
            var zz = Regex.IsMatch(s, "^((25[0-5]|2[0-4]\\d|((1\\d{2})|([1-9]?\\d)))\\.){3}(25[0-5]|2[0-4]\\d|((1\\d{2})|([1-9]?\\d)))$");
            if (zz==true)
            {
                return s;
            }
            else
            {
                return "";
            }
        }

效果图：