Use composed map in AutoMapper

Question

Suppose my AutoMapper configuration knows how to map from type T1 to type T2 and from T2 to type T3. I then have the following. It works:

public static class MapperExtensions
{
    public static T3 MapVia<T1, T2, T3>(this IMapper mapper, T1 t1) {
        var t2 = mapper.Map<T2>(t1);
        var t3 = mapper.Map<T3>(t2);
        return t3;
    }
    /// <summary> The calling code needs to ensure that t1 is of a type that the mapper knows how to map to type T2.</summary> 
    public static T3 MapVia<T2, T3>(this IMapper mapper, object t1) {
        var t2 = mapper.Map<T2>(t1);
        var t3 = mapper.Map<T3>(t2);
        return t3;
    }
}

My question is whether it is possible to bypass the middle type? I would love to be able to do something in my configuration to tell it "Generate a map from T1 to T3 that is the composition of your map from T1 to T2 and your map from T2 to T3." Then I could just map from T1 to T3 normally.

There are times when T2 is large, which may make this a performance issue. There are also cases where T2 is not particularly large.

There's nothing built in. – Lucian Bargaoanu Mar 02 '18 at 17:17 — Lucian Bargaoanu, Mar 02 '18 at 17:17

score 0 · Answer 1 · answered Mar 02 '18 at 17:22

0

Just converting Lucian Bargaoanu's comment to an answer here: There is no built-in way to do that.

answered Mar 02 '18 at 17:22

WhatGoodIsAName

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Use composed map in AutoMapper

1 Answers1