c# - How do I handle nested NPoco objects that may be null? -

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i using npoco object mapping database. have following entities:

public abstract class namedentity {     public int id { get; set; }     public string name { get; set; } }  public class person : namedentity {     public office office { get; set; } }  public class office : namedentity {     public address address { get; set; }     public organisation parentorganisation { get; set; } }  public class address {      public string addressline1 { get; set; } }  public class organisation : namedentity { }

and retrieving objects using npoco in repository:

var people = context.fetch<person, office, address, organisation>(sql);

this working fine, except case person not have office, in case result of left join in sql query returns null office, address , organisation columns.

in situation, unhandled exception thrown in npoco:

system.reflection.targetinvocationexception:  exception has been thrown target of invocation.  ---> system.nullreferenceexception:  object reference not set instance of object. @ poco_automapper(person , office , address , organisation ) --- end of inner exception stack trace --- @ system.runtimemethodhandle.invokemethod(object target, object[] arguments, signature sig, boolean constructor) @ system.reflection.runtimemethodinfo.unsafeinvokeinternal(object obj, object[] parameters, object[] arguments) @ system.delegate.dynamicinvokeimpl(object[] args) @ npoco.multipocofactory.callcallback[tret](delegate callback, idatareader dr, int32 count) @ npoco.multipocofactory.<>c__displayclassa`1.<createmultipocofactory>b__9(idatareader reader, delegate arg3) @ npoco.database.<query>d__14`1.movenext()

is there way handle situation? or have resort flattened object, or separate database calls?

this has been fixed in npoco 2.2.40.
reporting it.


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