wait: it should be as follows:
Code:
 public class BatchInfo
    {
        public delegate void StatusMessageChangeHandle(object tmp, StatusMessageChangeEventArgs e);

        private  BatchInfo.StatusMessageChangeHandle _StatusMessageChange;
        public event BatchInfo.StatusMessageChangeHandle StatusMessageChange
        {
            add
            {
                this._StatusMessageChange = (BatchInfo.StatusMessageChangeHandle)Delegate.Combine(this._StatusMessageChange, value);
            }
            remove
            {
                this._StatusMessageChange = (BatchInfo.StatusMessageChangeHandle)Delegate.Remove(this._StatusMessageChange, value);
            }
        }

    }