Compare crm id sdk early bound issue

Question

I try to compare 2 Guid in Linq to Crm request and it's not working. I don't see why:

Guid IdThematique = new Guid(ddlThematique);
Sollicitations = Sollicitations.Where(i => i.Sollicitation.SubjectId.Id == IdThematique);

This is the catched:

System.NullReferenceException: La référence d'objet n'est pas définie à une instance d'un objet. à XXX dans XXX 74 à System.Linq.Enumerable.WhereListIterator1.MoveNext() à System.Linq.Buffer1..ctor(IEnumerable1 source) à System.Linq.OrderedEnumerable1.d__0.MoveNext() à System.Linq.Enumerable.Count[TSource](IEnumerable`1 source) à xxx dans xxx 200

Thank you

Daryl Daryl · Accepted Answer · 2013-06-07T12:12:22

I'll agree with Mario, but I'd make it an extension method:

More concise version:

public static class EntityReferenceExtensions{
    public static Guid GetIdOrDefault(this EntityReference entity){
        return (entity ?? new EntityReference()).Id;
    }
}

Arguably more readable version:

public static class EntityReferenceExtensions{
    public static Guid GetIdOrDefault(this EntityReference entity){
        if(entity == null){
            return Guid.Empty;
        } else {
            return entity.Id;
        }
    }
}

But with the extension method, you could handle any Entity Reference of any Entity object (early or late bound)

Sollicitations.Where(i => (i.Sollicitation.SubjectId.GetIdOrDefault() == IdThematique))

Although now that I think about it, I don't think that this works for linq to CRM. Just Linq to Objects.

Compare crm id sdk early bound issue

3 Answers