private void buttonLogin_Click(object sender, EventArgs e)
 {
     ServiceReference1.User user = new ServiceReference1.User();
     user.UserLogin    = textBoxUserLogin.Text;
     user.UserPassword = textBoxUserPassword.Text;
     if (WorkWithDatabase.client.ConfirmUser(user))
     {
         User.userLogin    = user.UserLogin;
         User.userPassword = user.UserPassword;
         this.Close();
     }
     else
     {
         MessageBox.Show("Error user name or user password!");
     }
 }
 private void buttonRegistration_Click(object sender, EventArgs e)
 {
     ServiceReference1.User user = new ServiceReference1.User();
     user.UserLogin    = textBoxUserLogin.Text;
     user.UserPassword = textBoxUserPassword.Text;
     if (WorkWithDatabase.client.ConfirmUser(user))
     {
         MessageBox.Show("Error user name!\nThis user already exists!");
     }
     else
     {
         if (WorkWithDatabase.client.AddUser(user))
         {
             User.userLogin    = user.UserLogin;
             User.userPassword = user.UserPassword;
             this.Close();
         }
     }
 }