private void bttnInsertSkill_Click(object sender, EventArgs e) { SkillManage skilllist = new SkillManage(); if (cbboxInsertSkills.Visible == false) { cbboxInsertSkills.Visible = true; cbboxInsertSkills.Items.Clear(); foreach (Skills skill in skilllist.GetAllSkill()) { cbboxInsertSkills.Items.Add(skill.SkillName); } } if (cbboxInsertSkills.Visible == true) { } }