private async Task OnRegister()
        {
            Message = string.Empty;

            if (string.IsNullOrEmpty(UserName))
            {
                Message = "Please enter user name";
                return;
            }

            if (UserName.Length < 6)
            {
                Message = "Please enter valid user name";
                return;
            }

            if (string.IsNullOrEmpty(Password))
            {
                Message = "Please enter Password";
                return;
            }

            if (Password.Length < 4)
            {
                Message = "Please enter valid Password";
                return;
            }

            await PageNavigation.NavigateBackAsync($"{UserName} is Registered Succesfully");
        }
 protected virtual async Task OnNavigateBackAsync(object parameter = null)
 {
     await PageNavigation.NavigateBackAsync();
 }