将值从BackgroundWorker DoWork 传递到BackgroundWorker Completed

我如何传递一个值BackgroundWorker DoWork to BackgroundWorker Completed? Since BackgroundWorker Completed不被调用BackgroundWorker DoWork我不知道如何做到这一点，除了声明public variable。本质上，我想要BackgroundWorker Completed接受通过ByVal一个变量来自BackgroundWorker DoWork.

当您声明您的DoWork函数，请注意它内置了一些方便的参数：

Private Sub backgroundWorker1_DoWork(sender As Object, e As DoWorkEventArgs) _
                                                  Handles backgroundWorker1.DoWork

并且还注意到类似的论点RunWorkerCompleted处理程序：

Private Sub backgroundWorker1_RunWorkerCompleted(ByVal sender As Object, _
                                          ByVal e As RunWorkerCompletedEventArgs) _
                                       Handles backgroundWorker1.RunWorkerCompleted

至关重要的是，您可以访问e.Result，它可以是任何对象，在RunWorkerCompletedEventArgs，并且e.Result在你的DoWorkEventArgs- 当方法完成时，后者将传递给前者，因此在工作方法结束时只需设置：

e.Result = myResult

然后在你的RunWorkerCompleted处理程序您也可以通过以下方式访问它：

if e.Result = (whatever) then 
    .... etc

参考 ：

RunWorkerCompletedEventArgs.Result 属性：MSDN http://msdn.microsoft.com/en-us/library/system.componentmodel.runworkercompletedeventargs.result%28v=vs.85%29.aspx

DoWorkEventArgs.Result 属性：MSDN http://msdn.microsoft.com/en-us/library/system.componentmodel.doworkeventargs.result%28v=vs.85%29.aspx