Is String culture info important for comparison if the user will never modify those strings

Question

When comparing hard-coded Strings that the User will see but not modify/change, is the culture info important.

I would assume not, but I just want to be safe.

Example:

static void Main()
{
    string hardString = "IAMHardCodei";
    string hardString2 = "IamHardCodei";
    //Compare hardString and hardString2, ignoring case, 
    //and then do stuff based on that result
}

It's always important, even if the user doesn't see or modify it. It all depends on what kind of data you're manipulating. — Thomas Levesque, Apr 25 '15 at 16:04
@ThomasLevesque I added an example to be more clear. The values are hard coded in by me — JackBarn, Apr 25 '15 at 16:09
What if the two strings aren't equal in say, Chinese? Not true here but depending on the strings it could be. — dmeglio, Apr 25 '15 at 16:13

score 1 · Answer 1 · answered Apr 25 '15 at 16:10

1

You can use InvariantCultureIgnoreCase for the comparing

hardString.Equals(hardString2, StringComparison.InvariantCultureIgnoreCase);

answered Apr 25 '15 at 16:10

VMAtm

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Asad Saeeduddin · Answer 2 · 2015-04-25T16:21:59.107

Culture rules are relevant even for hardcoded strings if you're relying on the default CurrentCulture when doing comparisons. Here's a textbook example out of the MSDN documentation:

Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US")
Debug.Assert("file" == "FILE".ToLower()); // Passes

Thread.CurrentThread.CurrentCulture = new CultureInfo("tr-TR");
Debug.Assert("file" == "FILE".ToLower()); // Fails

With case insensitive comparison, your users computers in Turkey don't think file and FILE are identical, whereas in the US they are identical.

score 0 · Accepted Answer · edited May 23 '17 at 12:06

0

The general recommendation for string comparisons when they are "programmatic only strings" (i.e. as you specified they are not usable or editable by the user directly is the: StringComparison.Ordinal[IgnoreCase].

See this SO post (of which this is probably a duplicate): Which is generally best to use -- StringComparison.OrdinalIgnoreCase or StringComparison.InvariantCultureIgnoreCase?

edited May 23 '17 at 12:06

Community

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answered Apr 25 '15 at 16:10

CodingGorilla

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@VMAtm It always depends on the very specific implementation needs, that was why I prefixed it with: "The general recommendation". :) – CodingGorilla Apr 25 '15 at 16:14

Is String culture info important for comparison if the user will never modify those strings

3 Answers3