c# 用*号隐藏用户名、手机号的中间部分

        /// 

        /// 用*号隐藏部分用户名、手机号
        /// 
        /// 
        /// 
        public static string ConverUserNameToAnonymous(this string userName)
        {
            string userNameAfterReplaced;
            try
            {
                int nameLength = userName.Length;
                if (nameLength <= 2 && nameLength >= 1)
                {
                    if (nameLength == 1)
                    {
                        userNameAfterReplaced = "*";
                    }
                    else
                    {
                        userNameAfterReplaced = "**";
                    }
                }
                else
                {
                    int num1, num2, num3;
                    num2 = (int)Math.Ceiling((double)nameLength / 3);
                    num1 = (int)Math.Floor((double)nameLength / 3);
                    num3 = nameLength - num1 - num2;
                    StringBuilder starStr = new StringBuilder();
                    for (int i = 0; i < num2; i++)
                    {
                        starStr.Append("*");
                    }
                    userNameAfterReplaced = $"{userName.Substring(0, num1)}{starStr}{userName.Substring(num1 + num2, num3)}";
                }
            }
            catch (Exception)
            {
                userNameAfterReplaced = userName;
            }
            return userNameAfterReplaced;
        }

引用示例：

user.NickName = user.NickName.ConverUserNameToAnonymous();