int IUnknown.Release()
{
if (NativePointer == IntPtr.Zero)
{
throw new InvalidOperationException("COM Object pointer is null");
}
return(PortableMarshal.Release(NativePointer));
}
/// <summary>
/// Queries a managed object for a particular COM interface support.
/// </summary>
///<typeparam name="T">The type of the COM interface to query</typeparam>
/// <param name="comPointer">A pointer to a COM object.</param>
///<returns>An instance of the queried interface</returns>
/// <msdn-id>ms682521</msdn-id>
/// <unmanaged>IUnknown::QueryInterface</unmanaged>
/// <unmanaged-short>IUnknown::QueryInterface</unmanaged-short>
public static T QueryInterfaceOrNull <T>(IntPtr comPointer) where T : ComObject
{
if (comPointer == IntPtr.Zero)
{
return(null);
}
var guid = Utilities.GetGuidFromType(typeof(T));
IntPtr pointerT;
var result = (Result)PortableMarshal.QueryInterface(comPointer, ref guid, out pointerT);
return((result.Failure) ? null : FromPointerUnsafe <T>(pointerT));
}
Result IUnknown.QueryInterface(ref Guid guid, out IntPtr comObject)
{
return(PortableMarshal.QueryInterface(NativePointer, ref guid, out comObject));
}