发生 UnauthorizedAccessException 时如何跳过目录或文件

Question

代码如下。我试图从sDirPath 的特定路径获取文件，然后存储在树视图中，基本上是制作一个自定义文件夹浏览器对话框。但问题是，当我得到无法访问的系统文件或文件夹时，我得到UnauthorizedAccessException。它发生在文件夹或文件上，如隐藏和系统文件夹或文件，例如 C:\ 中的 $recyle.bin 或文档和设置的快捷方式。我只想跳过这些文件夹或文件。我不想拿它们。

Dim sAllfiles() As String = Directory.GetFiles(sDirPath, "*.*")
For Each sfile As String In sAllfiles          
    Dim objFileInformation As FileInfo = New FileInfo(sfile)
    Dim tnTreeNodeSub As TreeNode
    tnTreeNodeSub=tnTreeNodeRootDirectory.Nodes.Add(objFileInformation.Name)
Next    

Answer 1

Try .. Catch 语句正是为了这个。

例如，这只会忽略UnauthorizedAccessException。任何其他异常仍然会终止循环。

Dim sAllfiles() As String = Directory.GetFiles(sDirPath, "*.*")
For Each sfile As String In sAllfiles
    Try
        Dim objFileInformation As FileInfo = New FileInfo(sfile)
        Dim tnTreeNodeSub As TreeNode
        tnTreeNodeSub=tnTreeNodeRootDirectory.Nodes.Add(objFileInformation.Name)
    Catch ex As UnauthorizedAccessException
        Continue For 'Ignore the exception and move on
    End Try
Next

Answer 2

对 Gabriel Luci 的回答的修改：

Try
    Dim sAllfiles() As String = Directory.GetFiles(sDirPath, "*.*")
    For Each sfile As String In sAllfiles
        Try
            Dim objFileInformation As FileInfo = New FileInfo(sfile)
            Dim tnTreeNodeSub As TreeNode
            tnTreeNodeSub=tnTreeNodeRootDirectory.Nodes.Add(objFileInformation.Name)
        Catch ex As UnauthorizedAccessException
            Continue For 'Ignore the exception and move on
        End Try
    Next
Catch ex As UnauthorizedAccessException
    'Ignore the exception and move on
End Try

这样做并添加一个额外的捕获将有所帮助，如果您直接在 sDirPath 中提供无法访问的路径，如果您不添加它将关闭您的应用程序。