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Start your free trialAaron Selonke
10,323 PointsDifference between Union() and Concat()
What's the difference between using Union and Concat, they seem to produce the same sequence?
It seems like colors.Concat(birds.Select(i => i.Color).Distinct()); and colors.Union(birds.Select(i => i.Color)); are the same
but Carling still uses the .Distinct() when using Union() .... ? It seems like Union() already produces a distinct color sequence and that is the difference.
1 Answer
Steven Parker
231,198 PointsYou're right, you don't need Distinct when you use Union. It doesn't hurt, but it doesn't need to be there.
And, that's basically the difference between Union and Concat. With Union you get no duplicates, but with Concat you may.