Setting a WinRt AdvertisementFilter() to a substring of LocalName - c++

Question

C++, WinRT, VS2017, Win10
I create a watcher to look for my Bluetooth LE device with
BluetoothLEAdvertisementWatcher watcher;
Now I want to set a filter for for the device that I am specifically looking for. Let's say that the LocalName for the device is "MyDevice_ABC1234". I can do this with
watcher.AdvertisementFilter().Advertisement().LocalName().c_str() == L"MyDevice_ABC1234";
But what I really want to do is set the filter to the manufacture's name and not the specific model number. I want to filter for "MyDevice" being in the LocalName. This would be easy enough given the luxury of a few lines of code but how would it be done in the context of
watcher.AdvertisementFilter().Advertisement().LocalName()
LocalName() has an operator for basic_string_view which has a find() method but for the life of me I can't get that to work properly. The find() is supposed to return the npos so I tried:
watcher.AdvertisementFilter().Advertisement().LocalName().operator std::basic_string_view<wchar_t, std::char_traits<wchar_t>>.find("MyDevice") == 8;
I actually tried this as simple code so I could debug the results with
hstring hstrLocalName = L"MyDevice_aBC1234";
bool bFind = hstrLocalName.operator std::basic_string_view<wchar_t, std::char_traits<wchar_t>>.find("MyDevice", 0) == 8;
and also
int iFind = hstrLocalName.operator std::basic_string_view<wchar_t, std::char_traits<wchar_t>>.find("MyDevice", 0);
But neither of these worked. They compiled but just never executed. Is there a way to get the basic_string_view.find() to work or would there be a better way to do this?

Answer 1

I see now, that when I do use the method mentioned above from StackOverflow here, it does filter for the LocalName that I set. However, and I remember this warning from the docs somewhere, that some advertisement packets come with the local name but not Uuids and visa versa. As it happenes, that is why I thought the filter was catching nothing. I was ignoring any packets that did not have services and these were the ones with the LocalName. Catch22.
For what it is worth, here is the method for setting a filter mentioned in the link above that also worked for me (with caveats)
auto filter = BluetoothLEAdvertisementFilter();
auto advert = BluetoothLEAdvertisement();
advert.LocalName(L"MyDevice_ABC1234");
filter.Advertisement(advert);
watcher.AdvertisementFilter(filter);