This event occurs on a worker thread.

This event occurs when the RunWorkerAsync method is called on this BackgroundWorker, providing on opportunity to perform work on a worker thread.

You must be careful not to manipulate any UI thread objects in your DoWork event handler - you can pass information between the UI and worker threads through the arguments of the DoWork, ProgressChanged, and RunWorkerCompleted event handlers.

If an exception is thrown within the DoWork event handler and is not caught within that scope, then in addition to the event handler terminating, the Error will be set with the exception. Any exceptions caught within the DoWork event handler will not be set into this property and therefore should be handled appropriately or re-thrown in order to respond to the exception in the UI if required.