識別FileSystemWatcher的父級

我的主表單中有一個 TabControl，每個 TabPage 都是動態添加的表單。這些（子）表單包含嚴格的控制元件（文本框、復選框等）以及 FileSystemWatcher。

在 TabPage 中添加表單時，FileSystemWatcher 使用路徑、過濾器等進行初始化，并且 EnableRaisingEvents 設定為 true。

這里是這部分的代碼（來自我的主要形式）：

Private Sub ApplyConfig
    For Each w As ClsCfgWatcher In MyWatchers
       '// create TabPage
       Call CreateTabPageWatcher(w)
    Next
End Sub

Private Sub CreateTabPageWatcher(w As ClsCfgWatcher)
    '// add tabpage
    TabWatcher.TabPages.Add(w.Name)
    Dim tp As TabPage = TabWatcher.TabPages(w.Name)
    With tp
        .Text = w.Name
        .UseVisualStyleBackColor = True
    End With

    '// adding form
    Dim f As New FrmCfgWatcher With {
        .TopLevel = False,
        .Anchor = AnchorStyles.Right Or AnchorStyles.Left Or AnchorStyles.Top Or AnchorStyles.Bottom,
        .Width = TabWatcher.SelectedTab.Width,
        .Height = TabWatcher.SelectedTab.Height
    }
    tp.Controls.Add(f)
    f.Show()

    '// write values to form from config
    With f
        .TxtName.Text = w.Name
        .TxtPath.Text = w.Path
        .CbxSubDirs.Checked = w.IncludeSubdirs
        .TxtFilter.Text = w.Filter

        .TxtCommand.Text = w.ActionCommand
        .TxtParameter.Text = w.ActionParameter
        .TxtWorkingDir.Text = w.ActionWorkingDir

        '// create FilesystemWatcher
        .Fsw = New FileSystemWatcher With {
                .Path = w.Path,
                .Filter = w.Filter,
                .IncludeSubdirectories = w.IncludeSubdirs,
                .NotifyFilter = DirectCast(w.NotifyFilter, NotifyFilters)
                }

        AddHandler w.Watcher.Created, AddressOf Fsw_Event
        AddHandler w.Watcher.Changed, AddressOf Fsw_Event
        AddHandler w.Watcher.Renamed, AddressOf Fsw_Event
        AddHandler w.Watcher.Deleted, AddressOf Fsw_Event

        w.Watcher.EnableRaisingEvents = True
    End With
End Sub

事件確實按預期引發，但現在我需要知道究竟是哪個 FileSystemWatcher 引發的？例如來自哪個 TabPage，因為我需要來自處理事件的子中的那個 Tabpage 的一些資訊。

更多代碼（來自標簽頁中的表單）：

Private Sub Fsw_Event(sender As Object, e As FileSystemEventArgs)
If e.FullPath > "" Then
    Dim sCmd As String = [text from textbox on form]
End If
End Sub

我需要 FileSystemWatcher-Object 和我的 TabPage 或表單之間的一些鏈接，我不知道如何實作這一點。

任何人都可以幫忙嗎？

uj5u.com熱心網友回復：

有幾種技術可以做到這一點。取決于個人需要，其中一個人可以使用。在您的情況下，我認為一種方法可能是您可以創建一個繼承為基類的自定義類FileSystemWatcher。

此時，您可以Name使用包含FileSystemWatcher. 在您的事件處理程式中，您可以攔截Name然后根據引發事件的物件的名稱執行代碼。

這里有一個例子：

Option Strict On
Imports System.IO


Public Class Form1


    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        CreateFSW()
    End Sub

    Sub CreateFSW()

        Dim Fsw = New CustomFSW With {
                .Name = "Tab1", 'Adding this you can specify the object is sending the event
                .Path = "C:\Users\Username\Desktop\Test\",
                .Filter = "*.*",
                .IncludeSubdirectories = True,
                .EnableRaisingEvents = True
                }


        AddHandler Fsw.Created, AddressOf Fsw_Event
        AddHandler Fsw.Changed, AddressOf Fsw_Event
        AddHandler Fsw.Renamed, AddressOf Fsw_Event
        AddHandler Fsw.Deleted, AddressOf Fsw_Event


    End Sub

    Private Class CustomFSW
        Inherits FileSystemWatcher
        Public Property Name As String
    End Class


    Private Sub Fsw_Event(sender As Object, e As FileSystemEventArgs)
        Dim FSW As CustomFSW = CType(sender, CustomFSW)
        If Not String.IsNullOrEmpty(FSW.Name) Then
            Select Case FSW.Name
                Case "Tab1"
                    'Do something
                    Debug.WriteLine("Event generated from: " & FSW.Name)

                Case "Tab2"
                    'Do something else 
                    Debug.WriteLine("Event generated from: " & FSW.Name)

            End Select
        End If

    End Sub


End Class

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