optgroup with all option
问题 my select option group is like <select multiple class="form-control form-white" data-placeholder="Select Courses"> <option value="all">All</option> <optgroup label="Play School"> <option value="1">All</option> <option value="2">Sec A</option> <option value="3">Sec B</option> </optgroup> <optgroup label="Nursery"> <option value="1">All</option> <option value="2">Sec A</option> <option value="3">Sec C</option> </optgroup> <optgroup label="LKG"> <option value="1">All</option> <option value="2"