急在线！

急急急，在线求助！！
1）原型
WINSETUPAPI
BOOL
WINAPI
SetupDiSetClassInstallParamsA(
        IN   HDEVINFO                                 DeviceInfoSet,
        IN   PSP_DEVINFO_DATA                 DeviceInfoData,                 OPTIONAL
        IN   PSP_CLASSINSTALL_HEADER   ClassInstallParams,         OPTIONAL
        IN   DWORD                                       ClassInstallParamsSize
        );

[DllImport( "setupapi.dll ",   SetLastError   =   true,   CharSet   =   CharSet.Auto)]static   extern   bool   SetupDiSetClassInstallParams(IntPtr   DeviceInfoSet,   ref   SP_DEVINFO_DATA   DeviceInfoData,   ref   SP_CLASSINSTALL_HEADER   ClassInstallParams,   int   ClassInstallParamsSize);

2）typedef   struct   _SP_CLASSINSTALL_HEADER   {
        DWORD               cbSize;
        DI_FUNCTION   InstallFunction;
}   SP_CLASSINSTALL_HEADER,   *PSP_CLASSINSTALL_HEADER;

  [StructLayout(LayoutKind.Sequential)]
                public   struct   SP_CLASSINSTALL_HEADER
                {
                        public   UInt32   cbSize;
                        public   uint   InstallFunction;
                }

3）typedef   struct   _SP_PROPCHANGE_PARAMS   {
        SP_CLASSINSTALL_HEADER   ClassInstallHeader;
        DWORD                                     StateChange;
        DWORD                                     Scope;
        DWORD                                     HwProfile;
}   SP_PROPCHANGE_PARAMS,   *PSP_PROPCHANGE_PARAMS;

    [StructLayout(LayoutKind.Sequential)]
                public   struct   SP_PROPCHANGE_PARAMS
                {
                        public   SP_CLASSINSTALL_HEADER   ClassInstallHeader;
                        public   UInt32   StateChange;
                        public   UInt32   Scope;
                        public   UInt32   HwProfile;
                }

问题：
1）这几个写法是否有问题？
2）
    SP_PROPCHANGE_PARAMS   spPropChangeParam   =   new   SP_PROPCHANGE_PARAMS();

                        spPropChangeParam.Scope   =   0x00000001;
                        spPropChangeParam.StateChange   =   0;
                        spPropChangeParam.ClassInstallHeader.cbSize   =   (UInt32)System.Runtime.InteropServices.Marshal.SizeOf(spPropChangeParam.ClassInstallHeader);
                        spPropChangeParam.ClassInstallHeader.InstallFunction   =   0x00000012;


                        SetupDiSetClassInstallParams(NewDeviceInfoSet,   ref   spData,   ref   spPropChangeParam.ClassInstallHeader,   System.Runtime.InteropServices.Marshal.SizeOf(spPropChangeParam));

调用不成功，GetLastError错误值87（参数不正确)，哪里出问题了？
NewDeviceInfoSet和spData参数应该没有问题。

谢谢




[解决办法]
from
http://www.devmedia.com.br/articles/viewcomp.asp?comp=4092&hl=
先看看别人是怎么用的

public const int DIGCF_PRESENT = 2;
public const int DIF_PROPERTYCHANGE = 0x00000012;
public const int DICS_FLAG_GLOBAL = 0x00000001;
public const int INVALID_HANDLE_VALUE = -1;
public const int DICS_ENABLE = 0x00000001;
public const int DICS_DISABLE = 0x00000002;
public const string USBVIDPID = @ "USB\VID_0403&PID_6001\A1000PRA ";

[StructLayout(LayoutKind.Sequential)]
public struct SP_CLASSINSTALL_HEADER
{
public int cbSize;
public int InstallFunction;
}

[StructLayout(LayoutKind.Sequential)]
public struct SP_PROPCHANGE_PARAMS
{
public SP_CLASSINSTALL_HEADER ClassInstallHeader;
public int StateChange;
public int Scope;
public int HwProfile;
public void Init()
{
ClassInstallHeader = new SP_CLASSINSTALL_HEADER();
}
}

[StructLayout(LayoutKind.Sequential)]
public struct SP_DEVINFO_DATA
{
public int cbSize;
public Guid ClassGuid;
public int DevInst;
public int Reserved;
}

[DllImport( "setupapi.dll ")]
public static extern bool SetupDiEnumDeviceInfo(
IntPtr DeviceInfoSet,
int Supplies,
ref SP_DEVINFO_DATA DeviceInfoData);

[DllImport( "setupapi.dll ")]
public static extern bool SetupDiSetClassInstallParams(
IntPtr DeviceInfoSet,
ref SP_DEVINFO_DATA DeviceInfoData,
ref SP_CLASSINSTALL_HEADER ClassInstallParams,
int ClassInstallParamsSize);

[DllImport( "setupapi.dll ")]
public static extern bool SetupDiCallClassInstaller(
int InstallFunction,
IntPtr DeviceInfoSet,
ref SP_DEVINFO_DATA DeviceInfoData);

static bool StateChange(int NewState, int SelectedItem, IntPtr hDevInfo)
{
SP_PROPCHANGE_PARAMS PropChangeParams;
SP_DEVINFO_DATA DeviceInfoData;
PropChangeParams = new SP_PROPCHANGE_PARAMS();
PropChangeParams.Init();
DeviceInfoData = new SP_DEVINFO_DATA();
PropChangeParams.ClassInstallHeader.cbSize
= Marshal.SizeOf(PropChangeParams.ClassInstallHeader);
DeviceInfoData.cbSize = Marshal.SizeOf(DeviceInfoData);
if (!SetupDiEnumDeviceInfo(hDevInfo, SelectedItem, ref DeviceInfoData))
return false;

PropChangeParams.ClassInstallHeader.InstallFunction = DIF_PROPERTYCHANGE;

PropChangeParams.Scope = DICS_FLAG_GLOBAL;
PropChangeParams.StateChange = NewState;
if (!SetupDiSetClassInstallParams(
hDevInfo,
ref DeviceInfoData,
ref PropChangeParams.ClassInstallHeader,
(int)Marshal.SizeOf(PropChangeParams)))
return false;
if (!SetupDiCallClassInstaller(
DIF_PROPERTYCHANGE,
hDevInfo,
ref DeviceInfoData))
return false;
return true;
}