如何判断写在类里面的回调函数执行完毕
某个回调函数写在类里

public class A
......
Private Delegate Sub CallAsyncDOExcelDelegate(ByRef lObjDataSet As DataSet)

Private Sub CallAsyncDOExcel(ByRef lObjDataSet As DataSet)

end sub

Public Sub ExportExcel(ByRef lObjDataSet As DataSet)

Dim doWork As New CallAsyncDOExcelDelegate(AddressOf CallAsyncDOExcel)
doWork.BeginInvoke(lObjDataSet，Nothing, Nothing)
end sub

end class


前台Form调用

Private Sub cmdExcel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdExcel.Click

a.ExportExcel(oDataSet)
End Sub

问题是：我在前台button click事件里，如何判断这个类中
的a.ExportExcel(oDataSet)异步执行完毕，
执行前，我要把button.enable=false
执行完，再吧button.enable=true




[解决办法]
你delegate有一个方法EndInvoke,可以获得委托执行完毕.你改一下人的程序就行了!