/// <summary>
/// check nickname Duplication
/// </summary>
/// <param name="nickname"></param>
/// <returns>true if nickName exist false if not </returns>
public async Task <bool> CheckNickNameDuplicationAsync(string nickname)
{
if (await _userDal.GetAppUserByNickNameAsync(nickname) == null)
{
return(false);
}
else
{
return(true);
}
}