private void LOGIN_Click(object sender, RoutedEventArgs e)
{
CheckLoginWindow.IsOpen = true;
if (_dal.CheckAccount(Login_UserName.Text, Login_Password.Password) != null)
{
TextBlock_Check_Login.Text = "Hello " + Login_UserName.Text;
_dal.SetUserIsOnline(Login_UserName.Text);
}
else
{
TextBlock_Check_Login.Text = "Invalid data!!";
}
}