Support ToDictionary within a projection "Select(x=>x..)"

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#25,986 2 comments 11 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
csharp
Domain
database

Research direction

The issue names no files, tests, or entry points. Start by locating query-translation tests for collection projections and compare the manual KeyValuePair projection with the requested ToDictionary form. Done means the ToDictionary form works inside the shown projection and has coverage for that query shape.

Written by the indexing model from the issue text.

Description

area-query customer-reported

I am trying to use projection of objects between database entities and DTOs and return an IQueryable for OData results to be filtered etc.

It would be great if we had a way to use ToDictionary within the projection of a collection. This is currently possible but very ugly.

context.Items
       .Select (item => new Ob { Dict = new Dictionary<string,string>(item.Collection.Select(x => new KeyValuePair<string, string>(x.PropA, x.PropB)) } ),

Ideally this could be achieved simply by doing :

context.Items
       .Select (item => new Ob { Dict = item.Collection.ToDictionary(x => x.PropA,  x => x.PropB) });
Dominant language
C#
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Forks
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Avg merge
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Merged PRs (30d)
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