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DataGridView.RowEnter事件中的Task.WaitAll（）导致DataError 参考Async/Await - Best Practices in Asynchronous Programming

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我正在使用Advanced DataGridView（https://github.com/davidegironi/advanceddatagridview）在我的应用程序中显示一些数据。

在RowEnter事件中，我创建如下任务：

Dim One As String = dgv.Item("Col1",e.RowIndex)
Dim Two As String = dgv.Item("Col2",e.RowIndex)
Dim Three As String = dgv.Item("Col3",e.RowIndex)

Dim tOne As Task(Of DataTable) = Task.Run(Function() Return GetData(One) End Function)
Dim tTwo As Task(Of DataTable) = Task.Run(Function() Return GetData(Two) End Function)
Dim tThree As Task(Of DataTable) = Task.Run(Function() Return GetData(Three) End Function)

Task.WaitAll(tOne,tTwo,tThree)

'Do stuff with the results of tasks to update other labels etc on the form
lblDate.Text = tOne.Result.Rows(0).Item("Date").ToString

这样做的原因是，如果GetData()函数花费5秒返回而不执行此操作，则将导致15秒的等待时间（5 + 5 + 5），而使用任务仅需5秒秒（或最慢的任务是什么）和Task.WaitAll将控制权交还给UI（不确定正确的术语），因此感觉有点敏捷。

但是，当我应用过滤器时，我反复遇到以下异常，其中[n]是任意数字，我已经看到-1向上的索引（似乎取决于可见行的数量？）：> 

System.IndexOutOfRangeException: Index [n] does not have a value.
   at System.Windows.Forms.CurrencyManager.get_Item(Int32 index)
   at System.Windows.Forms.DataGridView.DataGridViewDataConnection.GetError(Int32 boundColumnIndex,Int32 columnIndex,Int32 rowIndex)

如果我删除Task.WaitAll（）或同步执行功能，则不会出现上述错误。

我完全不知道该错误的根本原因是什么，或者我应该做些什么来避免该错误。

我见过this answer，但不确定如何应用。

chkxchkx 回答：DataGridView.RowEnter事件中的Task.WaitAll（）导致DataError 参考Async/Await - Best Practices in Asynchronous Programming

使用异步事件处理程序，然后使用Task.WhenAll

等待任务 
' Mark the event handler with Async so you can use Await in it.
Private Async Sub Grid_RowEnter(sender As Object,e As WhateverEventArgs)
    Dim One As String = dgv.Item("Col1",e.RowIndex)
    Dim Two As String = dgv.Item("Col2",e.RowIndex)
    Dim Three As String = dgv.Item("Col3",e.RowIndex)

    Dim tOne As Task(Of DataTable) = Task.Run(Function() Return GetData(One) End Function)
    Dim tTwo As Task(Of DataTable) = Task.Run(Function() Return GetData(Two) End Function)
    Dim tThree As Task(Of DataTable) = Task.Run(Function() Return GetData(Three) End Function)

    ' await all the tasks
    Await Task.WhenAll(tOne,tTwo,tThree)

    ' back on UI thread

    'Do stuff with the results of tasks to update other labels etc on the form
    lblDate.Text = tOne.Result.Rows(0).Item("Date").ToString

End Sub

参考Async/Await - Best Practices in Asynchronous Programming

multithreadingtaskvb.netwinforms
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