<input type="submit" class="btn btn-primary btn-block"  name="submissionbutton" value="Save" />
        <input type="submit" class="btn btn-primary btn-block" name="submissionbutton" value="Save & Exit" />

var button = Request.Form["submissionbutton"];
        model.Save(id, db);
        if (button == "Save & Exit")
        {
            return RedirectToAction("Index");
        }
        else
        {
            model = new EditEquipmentViewModel(id, db);
            return View(model);
        }

<button name="name" value="save" type="submit">Save</button>
<button name="name" value="saveexit" type="submit">Save & Exit</button>