c# - How do I perform a LINQ query to a database? -

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through method onnavigatedto () page int , make linq query list, taking items database in localstorage.

    protected override async void onnavigatedto(navigationeventargs e)     {         sqliteasyncconnection mussall = new sqliteasyncconnection("databasemusei.db");         var queryall = await mussall.table<musei>().tolistasync();         list<musei> museiall = new list<musei>();         foreach(musei mus in queryall)            {              museiall.add(mus);            }         idmusei = (int)e.parameter;         musei muss;         muss = museiall.where(x => x.id == idmusei).firstordefault();   //my code     }

but start reading read properties in created object, exception:

message = "object reference not set instance of object."

if on page directly object museums , do: mus = (museei) e.parameters; program works. problem?


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