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Start your free trialMaurice Abney
Courses Plus Student 9,859 PointsAnswer not correct
Not sure why this code is not correct. This is what was done in the video and it's also how it's done on multiple stackoverflow answers
using System.Collections.Generic;
using System.Linq;
namespace Treehouse.CodeChallenges
{
public static class ContainsAnyExtension
{
public static bool ContainsAny(this string source, IEnumerable<string> stringsToMatch)
{
return stringsToMatch.Any(s => s.Contains(source));
}
}
}
2 Answers
Steven Parker
231,198 PointsIt looks like you have your arguments reversed.
The challenge asks you to "identify if any of the stringsToMatch
are found as partial matches in the source string", but your code checks to see if the source string is found in any of the stringsToMatch
. You may have intended to do this:
return stringsToMatch.Any(s => source.Contains(s));
I have no idea how Allan got the original code to pass. The error was: "Bummer! I used the ContainsAny method and expected true, but got false."
Allan Clark
10,810 PointsI copied and pasted your code directly into the challenge window and it marked it as correct. What error are you getting?
Maurice Abney
Courses Plus Student 9,859 PointsThere was no error, just said that they tried a string and it returned false instead of true. I still dont understand what the difference between "s => s.Contains(source)" and "s => source.Contains(s)" though. It seems like they are supposed to be doing the same thing.
Maurice Abney
Courses Plus Student 9,859 PointsMaurice Abney
Courses Plus Student 9,859 PointsThis was the issue, thanks Steven!
Steven Parker
231,198 PointsSteven Parker
231,198 PointsYou said you were confused about the difference between "s => s.Contains(source)" and "s => source.Contains(s)". Maybe this would help. Imagine if you substitute "box" for "source" and "marbles" for "s".
So then "box.Contains(marbles)" would make sense, because your box can have marbles in it, but "marbles.Contains(box)" doesn't work because the marbles can't contain anything. Now I know it's not quite so simple when both items are strings, but the idea that we can expect one might contain the other but not vice-versa still holds.