我在VB.NET中调用Shell.BrowseForFolder因为我需要在rootFolder参数中传递一个任意路径。所以我实现了这样的目标:
Dim shellType As Type = Type.GetTypeFromProgID("Shell.Application")
Dim shell = Activator.CreateInstance(shellType)
然后我打电话给:
Dim folder = shell.BrowseForFolder(0, message, &H241, rootFolder)
它无法正常工作(根文件夹F:未使用)
但是如果我使用相同参数的反射:
Dim folder = shellType.InvokeMember("BrowseForFolder", _
BindingFlags.InvokeMethod, Nothing, shell, New Object() {0, message, &H241, _
rootFolder})
有效!
但对我来说,2次调用(InvokeMember和直接调用)应该产生类似的结果(参数是相同的)。发生了什么事?
修改
事实上,如果我调用ToString()或者我放了一个litteral:
,它就可以工作Dim folder = shell.BrowseForFolder(0, message, &H241, rootFolder.ToString())
或
Dim folder = shell.BrowseForFolder(0, message, &H241, "F:")
但是如果rootFolder是一个参数,它就不起作用,例如:
Function BrowseForFolder(ByVal message As String, ByVal rootFolder As String) As String
Dim shellType As Type = Type.GetTypeFromProgID("Shell.Application")
Dim shell = Activator.CreateInstance(shellType)
Dim folder = shell.BrowseForFolder(0, message, &H241, rootFolder)
If folder Is Nothing Then
Return ""
End If
Return folder.Self.Path
End Function
答案 0 :(得分:2)
我使用vs 2012在Windows 7 64位下重现此问题的唯一方法是在该变量中使用无效的rootFolder
,如空字符串或废话数据。
你可以在那一行做一个断点:
Dim folder = shell.BrowseForFolder(0, message, &H241, rootFolder)
并检查rootFolder
是什么?
找到了尝试的方法;
Dim folder = shell.BrowseForFolder(0, message, &H241, rootFolder.ToString())
我的代码:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim rootFolder As Object = "f:"
Dim shellType As Type = Type.GetTypeFromProgID("Shell.Application")
Dim shell = Activator.CreateInstance(shellType)
Dim folder = shell.BrowseForFolder(0, "message", &H241, rootFolder.ToString())
End Sub
答案 1 :(得分:1)
您可以直接使用folderBrowserDialog:
Dim f As New FolderBrowserDialog
f.SelectedPath = "f:"
f.ShowDialog()
虽然我看不到如何将它带到仅显示F: