Linq join without equals

c#, join, linq

Solution

You can use multiple from clauses to achieve a join

 var matches = from p in points
               from r in rectangles
               where r.Contains(p)
               select new { r, p };

Multiple from clauses are more flexible than the join syntax (see myth 5 of 10 LINQ myths). You need to learn only this one and all joins will be easy.

Problem

I have a list of rectangles and a list of points. I want to construct a LINQ query that will match the list of points with their corresponding rectangles. Something like this: ``` // Does not compile var matches = from rect in rectangles join point in points on rect.Contains(point) select new { rect, point }; ``` How does one accomplish something like this with LINQ? EDIT: My lists are equal size - I have one point to match with one rectangle, and the rectangles don't overlap. However, the point of the question isn't so much to solve this one specific problem. I'm interested, in general, how to join two lists on any condition other than simply 'equals'.

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