最近用C#写安装usb驱动，必须得调用API SetupCopyOEMInf：
BOOL WINAPI SetupCopyOEMInf(
_In_ PCTSTR SourceInfFileName,
_In_ PCTSTR OEMSourceMediaLocation,
_In_ DWORD OEMSourceMediaType,
_In_ DWORD CopyStyle,
_Out_opt_ PTSTR DestinationInfFileName,
_In_ DWORD DestinationInfFileNameSize,
_Out_opt_ PDWORD RequiredSize,
_Out_opt_ PTSTR DestinationInfFileNameComponent
);
于是在C#里这么写了：
[DllImport("setupapi.dll", SetLastError = true)]
private static extern bool SetupCopyOEMInf(
string SourceInfFileName,
string OEMSourceMediaLocation,
OemSourceMediaType OEMSourceMediaType,
OemCopyStyle CopyStyle,
out string DestinationInfFileName,
int DestinationInfFileNameSize,
int RequiredSize,
out string DestinationInfFileNameComponent
);
其中DestinationInfFileName代表驱动成功安装后，inf文件在C:\Windows\inf目录下的绝对路径，这个inf文件名字和原inf文件不一样，但是内容是一模一样的，不知道为啥inf驱动安装成功后会把inf文件换一个名字然后copy到C:\Windows\inf目录下？有高人解答下吗？
DestinationInfFileNameComponent代表copy到C:\Windows\inf目录下的那个inf的名字，这个很有用，调用SetupUninstallOEMInf卸载驱动的时候要用到这个名字。
然后我在C#中这么调用SetupCopyOEMInf：
unsafe
{
success = SetupCopyOEMInf(infPath, "", OemSourceMediaType.SPOST_PATH, OemCopyStyle.SP_COPY_NEWER, out destinationInfFileName, ,
, out destinationInfFileNameComponent);
}
260是文件目录的最大长度，查看log，C:\Windows\inf\setupapi.dev.log,可以成功安装，success为true，但是接下来的问题困扰了我好久，destinationInfFileNameComponent和destinationInfFileName始终都没有值，按照https://msdn.microsoft.com/en-us/library/aa376990.aspx上的说话，成功执行后会返回这俩值，destinationInfFileNameComponent是调用SetupUninstallOEMInf卸载驱动的必传参数，没有值就无法卸载了，google了半天没有解决，最后看别人用C++写的SetupCopyOEMInf，destinationInfFileName传的是一个长度为260的TCHAR数组，于是我把C#的SetupCopyOEMInf原型改为：
[DllImport("setupapi.dll", SetLastError = true)]
private static extern bool SetupCopyOEMInf(
string SourceInfFileName,
string OEMSourceMediaLocation,
OemSourceMediaType OEMSourceMediaType,
OemCopyStyle CopyStyle,
out char[] DestinationInfFileName,
int DestinationInfFileNameSize,
int RequiredSize,
out string DestinationInfFileNameComponent
);
然后把destinationInfFileName声明为一个260长度的char数组，但是调用会报executionexception的异常。后来把原型参数char[] destinationInfFileName前面的out去掉，destinationInfFileNameComponent的值终于正确得到了!!!!!!!!
但是destinationInfFileName依然无法得到，好歹有了一个，终于可以做卸载了，具体为什么可以了也不太清楚，为什么PTSTR DestinationInfFileName传递C#的string不对？传递char数组才可以，但是无法使用out，估计destinationInfFileNameComponent是在destinationInfFileName的基础上得到的，所以传递string类型的destinationInfFileNameComponent是可以的吧，糊涂了！
完美的解决方法：
原型：
[DllImport("setupapi.dll", SetLastError = true)]
private static extern bool SetupCopyOEMInf(
string SourceInfFileName,
string OEMSourceMediaLocation,
OemSourceMediaType OEMSourceMediaType,
OemCopyStyle CopyStyle,
StringBuilder DestinationInfFileName,
int DestinationInfFileNameSize,
int RequiredSize,
out string DestinationInfFileNameComponent
);
调用：
string msg = "";
int size = ;
StringBuilder destinationInfFileName_builder = new StringBuilder();
unsafe
{
success = SetupCopyOEMInf(infPath, "", OemSourceMediaType.SPOST_PATH, OemCopyStyle.SP_COPY_NEWER, destinationInfFileName_builder, destinationInfFileName_builder.Capacity,
,out destinationInfFileNameComponent);
}
if (!success)
{
var errorCode = Marshal.GetLastWin32Error();
var errorString = new Win32Exception(errorCode).Message;
msg = errorString;
}
把destinationInfFileName设成一个有260个字符长的空stringbuilder，stringbuilder是按引用传值，所以不需要添加out或者ref了，但是destinationInfFileNameComponent必须是out string，设成stringbuilder会是乱码。
这样destinationInfFileNameComponent和destinationInfFileName都能正确得到了！这样是不是可以猜测，C#调用WINAPI，如果函数原型参数是_Out_opt_ PTSTR，并且这个PTSTR要有长度输入，在C#中就可以声明成StringBuilder？
参考：
http://www.pinvoke.net/default.aspx/setupapi.SetupCopyOEMInf
https://msdn.microsoft.com/en-us/library/aa376990.aspx
http://*.com/questions/18404660/how-to-use-setupcopyoeminf-during-installer