TdConnection supports the OpenAsync method introduced in .NET Framework 4.5. This method returns a System.Threading.Tasks.Task that may execute asynchronously.
The application may simply await the task to complete, during which time the application thread will not be blocked, or it may continue with other processing and periodically check to see whether the task has completed, by checking its IsCompleted property.
Each asynchronous method takes an optional System.Threading.CancellationToken that can be used to request cancellation of the operation if it is taking too long.
The State of the TdConnection will be Connecting while the OpenAsync method is in progress.
A second OpenAsync, or Open, method will fail if executed while OpenAsync is executing for the same TdConnection.