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Accessing C# Anonymous Type Objects

How do i access objects of an anonymous type outside the scope where its declared?

for e.g.

void FuncB()
{
var obj = FuncA();
Console.WriteLine(obj.Name);
}

??? FuncA()
{
var a = (from e in DB.Entities
where e.Id == 1
select new {Id = e.Id, Name = e.Name}).FirstOrDefault();

return a;
}
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1 Answer

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by (71.8m points)

As the other answers have stated, you really shouldn't do this. But, if you insist, then there's a nasty hack known as "cast by example" which will allow you to do it. The technique is mentioned in a couple of articles, here and here.

public void FuncB()
{
    var example = new { Id = 0, Name = string.Empty };

    var obj = CastByExample(FuncA(), example);
    Console.WriteLine(obj.Name);
}

private object FuncA()
{
    var a = from e in DB.Entities
            where e.Id == 1
            select new { Id = e.Id, Name = e.Name };

    return a.FirstOrDefault();
}

private T CastByExample<T>(object target, T example)
{
    return (T)target;
}

(I can't take the credit for this hack, although the author of one of those articles says that he doesn't want to be associated with it either. His name might be familiar.)


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