vb.net对事件源头一次性清除事件订阅列表

在VB.Net中，不能直接使用Event的名称 = nothing来清除所有事件订阅列表，需要使用事件实例，而事件实例是在事件名称+Event, 如eTestEvent = Nothing

Public Class Form1


    Public Event eTest As EventHandler


    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        RaiseEvent eTest(Me, EventArgs.Empty)
    End Sub


    Private _no As Integer = 0


    Private Sub eTest_Run(sender As System.Object, e As System.EventArgs)
        _no += 1
        Debug.Print(_no)
        TextBox1.Text = _no.ToString()
    End Sub


    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        AddHandler Me.eTest, AddressOf eTest_Run
        AddHandler Me.eTest, AddressOf eTest_Run
    End Sub


    Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
        eTestEvent = Nothing   '在事件后面加上Event才是事件实例,只有事件实例才能通过设置为Nothing来清除所有事件列表
    End Sub

End Class

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