private void BindNpcDropDownlist(int sceneId) { List <NpcMapMapping> NpcMapMappings = OperateRecordManager.NpcMapMappings = npcManager.Get(sceneId); if (NpcMapMappings != null) { NpcDropDownList.DataSource = NpcMapMappings; NpcDropDownList.DisplayMember = "npc_name"; NpcDropDownList.ValueMember = "npc_id"; } else { NpcDropDownList.DataSource = null; } }