I think you can, but it does involve a configuration switch [0]. The index accessor for arrays has always been allowed to be of type long, the runtime was the

I think you can, but it does involve a configuration switch [0]. The index accessor for arrays has always been allowed to be of type long, the runtime was the one causing the trouble. As for List<T>, it's still problematic since all the methods still accept an int. [0] https://docs.microsoft.com/en-us/dotnet/framework/configure-apps/file-schema/runtime/gcallowverylargeobjects-element https://docs.microsoft.com/en-us/dotnet/framework/configure-...