private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            panelClassData.Visible = true;
            pictureBox2.Visible = false; // show error pic
            buttonAdd.Enabled = true;

            Class = Classes.Find(g => (g.getClassName() == comboBoxClasses.Text));
            labelRegisterd.Text = Class.getClassListed().ToString();
            labelCapacity.Text = Class.getClassCapacity().ToString();
            labelInstructorNmae.Text = Class.getClassInstructor().getNameFirst() + " " + Class.getClassInstructor().getNameLast();
            labelDay.Text = Class.getTimeDay();
            labelHour.Text = Class.getTimeHours();
            if (Class.getClassListed() == Class.getClassCapacity())//  if no more space in class
            {
                pictureBox2.Visible = true; // show error pic
                buttonAdd.Enabled = false;
                MessageBox.Show("Class have reached maximum capacity");

            }
            else
            {
                pictureBox1.Visible = true; // show good pic

            }
            panelClassData.Visible = true;
        }
        private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            //check what the user choose and get the specific gymclass
            Class = allgymClasses.Find(g => (g.getClassName().Equals(comboBox1.Text)));
            if (Class != null)
            {
                labelClassName.Text = Class.getClassName();
                labelClassRagisterd.Text = Class.getClassListed().ToString();
                labelClassCapacity.Text = Class.getClassCapacity().ToString();
                labelInstructorName.Text = Class.getClassInstructor().getNameFirst() + " " + Class.getClassInstructor().getNameLast();
                label10.Text = Class.getTimeDay();
                label12.Text = Class.getTimeHours();
                //check if the customer already registered to the choosen class if he is switch the button text from add to delete
                if (Curr.getListGymClass().Any(g => g.getClassName().Equals(comboBox1.Text)))
                {
                    buttonAddSelected.Text = "Delete Selected";
                }
                else
                {
                    buttonAddSelected.Text = "Add Selected";
                }
            }
            else
            {
                labelClassName.Text ="";
                labelClassRagisterd.Text = "";
                labelClassCapacity.Text = "";
                labelInstructorName.Text = "";
                label10.Text = "";
                label12.Text = "";
            }







        }