无法获得SP_DEVICE_INTERFACE_DETAIL_DATA的工作 [英] Cant get SP_DEVICE_INTERFACE_DETAIL_DATA to work

问题描述

我整夜都在处理这个问题，而且我知道有很多参考主题列出了如何正确调用此函数，但是无论我如何仍然可以使它起作用，所以我希望有人可以帮助我.

我得到的错误是ErrorCode 1784(提供的用户缓冲区对于请求的操作无效.")，这是我的代码:

I have been dealing with this all night long, and i know that there are many references topics that list on how to properly call this function but no matter what i still can make it work so i hope someone can help me out.

The error I''m getting is ErrorCode 1784 ("The supplied user buffer is not valid for the requested operation.") and here is a my code:

  Const DIGCF_PRESENT As Integer = 2
  Const DIGCF_DEVICEINTERFACE As Integer = 16
  Public GUID_DISPLAY_DEVICE_ARRIVAL As Guid = Guid.Parse("{1CA05180-A699-450A-9A0C-DE4FBE3DDD89}")

  <StructLayout(LayoutKind.Sequential)> Structure SP_DEVICE_INTERFACE_DETAIL_DATA
    Public cbSize As Integer
    <MarshalAs(UnmanagedType.ByValTStr, SizeConst:=256)> Public DevicePath As String
  End Structure
  <StructLayout(LayoutKind.Sequential)> Structure SP_DEVICE_INTERFACE_DATA
    Public cbSize As Integer
    Public interfaceClassGuid As Guid
    Public Flags As Integer
    Private Reserved As IntPtr
  End Structure

  <dllimport("setupapi.dll",> _
  Shared Function SetupDiGetDeviceInterfaceDetail(ByVal DeviceInfoSet As IntPtr, ByRef DeviceInterfaceData As SP_DEVICE_INTERFACE_DATA, ByRef DeviceInterfaceDetailData As SP_DEVICE_INTERFACE_DETAIL_DATA, ByVal DeviceInterfaceDetailDataSize As Integer, ByRef RequiredSize As Integer, ByRef DeviceInfoData As SP_DEVICE_INTERFACE_DATA) As Boolean
  End Function
  <dllimport("setupapi.dll",> _
  Shared Function SetupDiEnumDeviceInterfaces(ByVal DeviceInfoSet As IntPtr, ByVal DeviceInfoData As Integer, ByVal InterfaceClassGuid As Guid, ByVal MemberIndex As UInteger, ByRef DeviceInterfaceData As SP_DEVICE_INTERFACE_DATA) As Boolean
  End Function
  <dllimport("setupapi.dll",> _
  Shared Function SetupDiGetClassDevs(ByVal ClassGuid As Guid, ByVal Enumerator As Integer, ByVal hwndParent As IntPtr, ByVal Flags As UInteger) As IntPtr
  End Function

Sub Tester

    Dim h As IntPtr = SetupDiGetClassDevs(GUID_DISPLAY_DEVICE_ARRIVAL, 0, IntPtr.Zero, DIGCF_PRESENT Or DIGCF_DEVICEINTERFACE)
    Dim memberIndex As UInteger = 0

    Dim dia As New SP_DEVICE_INTERFACE_DATA()
    dia.cbSize = Marshal.SizeOf(dia)

    If SetupDiEnumDeviceInterfaces(h, 0, GUID_DISPLAY_DEVICE_ARRIVAL, memberIndex, dia) Then

      Dim didd As New SP_DEVICE_INTERFACE_DETAIL_DATA()
      didd.cbSize = Marshal.SizeOf(didd)
      Dim needbytes As Integer = 0
      If Not SetupDiGetDeviceInterfaceDetail(h, dia, didd, didd.cbSize, needbytes, Nothing) Then
'Fails here, and even needbytes is set to 0

      End If
    End If
  End Sub

奇怪的是，我什至无法使NeedBytes正确填充，它总是返回0，我发现在Needbytes中获得适当值的唯一方法是进行初始调用，将大小设置为8(I''m运行64位)，这样，needbytes的返回值为216，这似乎是有效的，但是如果我尝试将大小设置为216，我仍然会遇到相同的错误.

我也一直在使用该结构的LayoutKind和Pack属性，但也没有成功，所以我真的没有主意，将不胜感激.

The strange part is that i cannot even get needBytes to be correctly populated, it always returns to 0, the only way i have found to get a proper value in needbytes is to make a initial call setting the size to 8 (I''m running 64 bits), this way, needbytes get returned with a value of 216, which seems valid, but if i try to set the size to 216 i still get the same error.

I have been playing with the LayoutKind and Pack properties of the structure without success as well, so I''m really out of ideas, any help would be really appreciated.

推荐答案

对P/Invoke.net上的大小分配有评论

There''s a comment against the Size assignment on P/Invoke.net

SP_DEVICE_INTERFACE_DETAIL_DATA didd = new SP_DEVICE_INTERFACE_DETAIL_DATA();
didd.cbSize = 4 + Marshal.SystemDefaultCharSize; // trust me :)

因此，可能值得检查代码中的赋值.

http://www.pinvoke.net/default.aspx/Structures/SP_DEVICE_INTERFACE_DETAIL_DATA.html [ ^ ]

艾伦.

So it''s probably worth checking the assigned value in your code.

http://www.pinvoke.net/default.aspx/Structures/SP_DEVICE_INTERFACE_DETAIL_DATA.html[^]

Alan.

尝试一下:

如果不是SetupDiGetDeviceInterfaceDetail(h，dia，IntPtr.Zero，0，needbytes，Nothing)然后

Try this:

If Not SetupDiGetDeviceInterfaceDetail(h, dia, IntPtr.Zero, 0, needbytes, Nothing) Then

这篇关于无法获得SP_DEVICE_INTERFACE_DETAIL_DATA的工作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！