/// <summary>
/// Asynchronous evaluation of a <see cref="Report"/>
/// </summary>
/// <remarks>
/// This method is used as the <see cref="WaitOrTimerCallback"/> delegate for the
/// <see cref="ThreadPool.RegisterWaitForSingleObject"/> version of the asynchonous call.
/// <para>
/// This just retrieves the state, casts it to <see cref="AsyncReportState"/> and executes the
/// <see cref="EvaluateReport"/> method, passing the values received. It locks on the received
/// <see cref="StringBuilder"/> to append the messages from evaluation.
/// </para>
/// </remarks>
/// <param name="state">State for the execution.</param>
/// <param name="timedOut">If the <see cref="WaitHandle"/> timed out.</param>
private void OnReportEvaluate(object state, bool timedOut)
{
AsyncReportState st = (AsyncReportState)state;
System.Diagnostics.Debug.WriteLine("Executing report on thread: " +
Thread.CurrentThread.GetHashCode());
lock (st.Builder)
{
st.Builder.Append(EvaluateReport(st.Report, st.Context));
}
}
/// <summary>
/// Callback for asynchonous delegate execution.
/// </summary>
/// <remarks>
/// This is the <see cref="AsyncCallback"/> to use when executing
/// asynchronously the <see cref="EvaluateReport"/> method.
/// It completes the call by calling EndInvoke, retrieving the results
/// and appending the messages to the <see cref="StringBuilder"/> received
/// in the <see cref="IAsyncResult.AsyncState"/> property.
/// </remarks>
/// <example>
/// This in an example of the delegate creation and asynchronous execution.
/// <code>AsyncReportEvaluate eval = new AsyncReportEvaluate(EvaluateReport);
/// eval.BeginInvoke(rpt, ctx, new AsyncCallback(OnReportCompleted), sb);
/// </code>
/// </example>
/// <param name="result">The object to extract state information from.</param>
private void OnReportCompleted(IAsyncResult result)
{
try
{
AsyncResult ar = (AsyncResult)result;
AsyncReportState st = (AsyncReportState)ar.AsyncState;
AsyncReportEvaluate eval = (AsyncReportEvaluate)ar.AsyncDelegate;
string res = eval.EndInvoke(ar);
if (res != String.Empty)
{
lock (st.Builder)
{
st.Builder.Append(res).Append(System.Environment.NewLine);
System.Diagnostics.Debug.WriteLine(res);
}
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.Fail(ex.ToString());
throw ex;
}
}