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我有ListView和for循环来填充项目，创建的每个项目都有类TSMPPConnection的实例，这个类有属性ConnectionItem来保存ListView项目，我想从类内更改项目文本，请求来自对象事件，当我直接更改项目文本时，它会引发异常

其他信息：跨线程操作无效：控件 “lstConnections”是从其所在线程以外的线程访问的 创建于

代表： 我使用委托实现了这一点，但同样的错误

 Delegate Sub dlg_WriteConnectionItemStatus(s As String)
    Sub WriteConnectionItemStatus(s As String)

        Dim dlg As New dlg_WriteConnectionItemStatus(AddressOf WriteConnectionItemStatus)
        dlg.Invoke(s)

        'there is no InvokeRequired to check if execution come from delgate and avoid infinite loop
        If ConnectionItem IsNot Nothing Then ConnectionItem.SubItems(6).Text = s

    End Sub

不需要调用方检查执行是否来自委托并避免无限循环

尝试1：使用具有相同结构的另一个子系统从原始子系统中的委托调用它

  Delegate Sub dlg_WriteConnectionItemStatus(s As String)
    Sub WriteConnectionItemStatus(s As String)

        Dim dlg As New dlg_WriteConnectionItemStatus(AddressOf WriteConnectionItemStatus_Interface)
        dlg.Invoke(s)

    End Sub

    Sub WriteConnectionItemStatus_Interface(s As String)

        If ConnectionItem IsNot Nothing Then ConnectionItem.SubItems(6).Text = s

    End Sub

---

相同错误

您必须调用控件或窗体，调用委托本身就等于直接调用它：

writeconnectionimstatus（）

您可以通过为此创建扩展方法来简化：

Imports System.Runtime.CompilerServices

Public Module Extensions
    <Extension()> _
    Public Sub InvokeIfRequired(ByVal Control As Control, ByVal Method As Action)
        If Control.InvokeRequired = True Then
            Control.Invoke(Method)
        Else
            Method.Invoke()
        End If
    End Sub
End Module

但是，如果您的目标是.NET 3.5或更低版本，则必须坚持学员：

Delegate Sub SetSubItemTextDelegate(Item As ListViewItem, Index As Integer, Text As String)

Sub WriteConnectionItemStatus(s As String)

    If ConnectionItem IsNot Nothing Then _
        ConnectionItem.ListView.InvokeIfRequired(New SetSubItemTextDelegate(AddressOf SetSubItemText), ConnectionItem, 6, s)
End Sub

Sub SetSubItemText(Item As ListViewItem, Index As Integer, Text As String) 'Generalized method for flexibility.
    Item.SubItems(Index).Text = Text
End Sub

Delegate Sub SetSubItemTextDelegate(Item As ListViewItem, Index As Integer, Text As String)

Sub WriteConnectionItemStatus(s As String)

    If ConnectionItem IsNot Nothing Then _
        ConnectionItem.ListView.InvokeIfRequired(New SetSubItemTextDelegate(AddressOf SetSubItemText), ConnectionItem, 6, s)
End Sub

Sub SetSubItemText(Item As ListViewItem, Index As Integer, Text As String) 'Generalized method for flexibility.
    Item.SubItems(Index).Text = Text
End Sub