/// <summary>
/// Wraps a <see cref="Task{TResult}" /> into the Begin method of an APM pattern.
/// </summary>
/// <typeparam name="TResult">The type of the result.</typeparam>
/// <param name="task">The task to wrap. May not be <c>null</c>.</param>
/// <param name="callback">The callback method passed into the Begin method of the APM pattern.</param>
/// <param name="state">The state passed into the Begin method of the APM pattern.</param>
/// <returns>
/// The asynchronous operation, to be returned by the Begin method of the APM pattern.
/// </returns>
public static IAsyncResult ToBegin <TResult>(Task <TResult> task, AsyncCallback callback, object state)
{
TaskCompletionSource <TResult> tcs = new TaskCompletionSource <TResult>(state, TaskCreationOptions.RunContinuationsAsynchronously);
SynchronizationContextSwitcher.NoContext(() => CompleteAsync(task, callback, tcs));
return(tcs.Task);
}
/// <summary>
/// Wraps a <see cref="Task"/> into the Begin method of an APM pattern.
/// </summary>
/// <param name="task">The task to wrap.</param>
/// <param name="callback">The callback method passed into the Begin method of the APM pattern.</param>
/// <param name="state">The state passed into the Begin method of the APM pattern.</param>
/// <returns>The asynchronous operation, to be returned by the Begin method of the APM pattern.</returns>
public static IAsyncResult ToBegin(Task task, AsyncCallback callback, object state)
{
var tcs = new TaskCompletionSource <object>(state, TaskCreationOptions.RunContinuationsAsynchronously);
using (SynchronizationContextSwitcher.NoContext())
CompleteAsync(task, callback, tcs);
return(tcs.Task);
}
public override Task <int> ReadAsync([NotNull] byte[] buffer, int offset, int count, CancellationToken token)
{
CheckDisposed();
return(SynchronizationContextSwitcher.NoContext(async() =>
{
count = Math.Min(count, _row.ColumnLen - _row.PosInColumn);
var read = await _row.Buffer.ReadAllBytes(buffer, offset, count, true, true);
_row.PosInColumn += read;
return read;
}));
}
