我正在尝试从单独的线程访问动态生成的控件。 但我的代码总是出现“堆栈溢出异常”。
我正在使用以下代码:
Private _workerThread As Threading.Thread
Private Sub Main_Load(sender As Object, e As System.EventArgs) Handles Me.Load
Dim Label As New Label
Label.Name = "Label1"
Label.Location = New System.Drawing.Point(12, 12)
Label.Text = String.Empty
Label.AutoSize = True
Controls.Add(Label)
_workerThread = New Threading.Thread(AddressOf DoWork)
_workerThread.Priority = Threading.ThreadPriority.BelowNormal
_workerThread.Start()
End Sub
Private Sub DoWork()
SetLabelText("Label1", "text")
End Sub
Delegate Sub SetLabelTextCallback(ByVal LabelName As String, ByVal text As String)
Private Sub SetLabelText(ByVal LabelName As String, ByVal text As String)
If CType(Me.Controls(LabelName), Label).InvokeRequired Then
Dim d As New SetLabelTextCallback(AddressOf SetLabelText)
d.Invoke(LabelName, text)
Else
CType(Me.Controls(LabelName), Label).Text = text
End If
End Sub
显然 InvokeRequired 永远不会变为 False。但我不明白为什么。 也许有人可以告诉我我做错了什么。
最佳答案
您没有在 Label 的线程上调用 SetLabelTextCallback 方法,
因此你会在同一个线程上再次记忆起 InvokeRequired 永远不会是 false
Delegate Sub SetLabelTextCallback(ByVal LabelName As String, ByVal text As String)
Private Sub SetLabelText(ByVal LabelName As String, ByVal text As String)
Dim l as Label = CType(Me.Controls(LabelName), Label)
if l.InvokeRequired then
Dim d As New SetLabelTextCallback(AddressOf SetLabelText)
l.Invoke(d, new Object() {LabelName, text} )
Else
l.Text = text
End If
End Sub
关于vb.net - 表单控件数组上的线程安全调用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/10865408/