resharper

Is there a noticable performance difference between using string interpolation: myString += $"{x:x2}"; vs String.Format()? myString += String.Format("{0:x2}", x); I am only asking because Resharper is prompting the fix, and I have been fooled before. Jeroen Vannevel Noticable is relative. However: string interpolation is turned into string.Format() at compile-time so they should end up with the same result. There are subtle differences though: as we can tell from this question, string concatenation in the format specifier results in an additional string.Concat() call. string interpolation is

Whenever I have local variables in a method, ReSharper suggests to convert them to constants: // instead of this: var s = "some string"; var flags = BindingFlags.Public | BindingFlags.Instance; // ReSharper suggest to use this: const string s = "some string"; const BindingFlags flags = BindingFlags.Public | BindingFlags.Instance; Given that these are really constant values (and not variables) I understand that ReSharper suggest to change them to const. But apart from that, is there any other advantage when using const (e.g. better performance) which justifies using const BindingFlags instead

Sometimes Resharper warns about: Possible multiple enumeration of IEnumerable There's an SO question on how to handle this issue , and the ReSharper site also explains things here . It has some sample code that tells you to do this instead: IEnumerable<string> names = GetNames().ToList(); My question is about this specific suggestion: won't this still result in enumerating through the collection twice in the 2 for-each loops? CodeCaster GetNames() returns an IEnumerable . So if you store that result: IEnumerable foo = GetNames(); Then every time you enumerate foo , the GetNames() method is

While using ReSharper, it suggested "Enable C# 6.0 support for this project". I foolishly clicked on it, and now as advertised it's giving me suggestions for C# 6.0 - which then give me errors as I am not using C# 6.0 in this project. How can I disable C# 6.0 support, returning it to how it was before? (Preferably without having to individually ignore specific suggestions) Click the project node in the Solution Explorer. Then look in the Property Grid (F4). You'll see a property named "C# Language Level". Set that to "Default" or your desired language level. TO disable it at once across the