根据string 看里面是否含有该项 然后删除

        private void DeleteListNoneSendEmail(string newEmails)
        {
            List<QQEntity> qqEntityListTemp = QqEntityList;//存放到临时list
            for (int i = 0; i < QqEntityList.Count; i++)
            {
                if (!newEmails.Contains(QqEntityList[i].Name))
                {
                    qqEntityListTemp.Remove(QqEntityList[i]);//删除临时的里面的项
                }
            }
            QqEntityList = qqEntityListTemp;//从新付给
        }