System.Net.Cache.CombinedReadStream.EndRead C# (CSharp) Method

        public override int EndRead(IAsyncResult asyncResult) {

            if (Interlocked.Decrement(ref m_ReadNesting) != 0) {
                Interlocked.Increment(ref m_ReadNesting);
                throw new InvalidOperationException(SR.GetString(SR.net_io_invalidendcall, "EndRead"));
            }

            if (asyncResult == null) {
                throw new ArgumentNullException("asyncResult");
            }

            InnerAsyncResult myResult = asyncResult as InnerAsyncResult;

            if (myResult == null) {
                // We are just passing IO down, although m_HeadEOF should be always true here.
                GlobalLog.Assert(m_HeadEOF, "CombinedReadStream::EndRead|m_HeadEOF is false and asyncResult is not of InnerAsyncResult type {0).", asyncResult.GetType().FullName);
                return m_HeadEOF? m_TailStream.EndRead(asyncResult): m_HeadStream.EndRead(asyncResult);
            }

            // this is our wrapped AsyncResult
            myResult.InternalWaitForCompletion();

            // Exception?
            if (myResult.Result is Exception) {
                throw (Exception)(myResult.Result);
            }

            // Report the count read
            return (int)myResult.Result;
        }