建立新的 BackgroundWorker 例項

BackgroundWorker 通常用於執行任務，有時耗時，而不會阻止 UI 執行緒。

// BackgroundWorker is part of the ComponentModel namespace.
using System.ComponentModel;

namespace BGWorkerExample 
{
     public partial class ExampleForm : Form 
     {

      // the following creates an instance of the BackgroundWorker named "bgWorker"
      BackgroundWorker bgWorker = new BackgroundWorker();

      public ExampleForm() { ...