Untitled

private void ExecuteLogin(object parameter)
{
    if (Role == "Teacher")
    {
        var teacher = _dataService.GetTeacher(Username, Password);
        if (teacher != null)
        {
            // Open Teacher Dashboard with logged-in teacher
            var teacherDashboard = new TeacherDashboard(teacher);
            teacherDashboard.Show();

            // Close the Login window
            CloseCurrentWindow(parameter);
        }
        else
        {
            MessageBox.Show("Invalid teacher credentials.");
        }
    }
    else if (Role == "Student")
    {
        var student = _dataService.GetStudent(Username, Password);
        if (student != null)
        {
            // Open Student Dashboard with logged-in student
            var studentDashboard = new StudentDashboard(student);
            studentDashboard.Show();

            // Close the Login window
            CloseCurrentWindow(parameter);
        }
        else
        {
            MessageBox.Show("Invalid student credentials.");
        }
    }
    else
    {
        MessageBox.Show("Invalid role selected.");
    }
}