Find a substring in a case-insensitive way - C# [duplicate]

Question

Possible Duplicate:
Case insensitive contains(string)

With Contains() method of String class a substring can be found. How to find a substring in a string in a case-insensitive manner?

Answer 1

You can use the IndexOf() method, which takes in a StringComparison type:

string s = "foobarbaz"; int index = s.IndexOf("BAR", StringComparison.CurrentCultureIgnoreCase); // index = 3 

If the string was not found, IndexOf() returns -1.

Answer 2

There's no case insensitive version. Use IndexOf instead (or a regex though that is not recommended and overkill).

string string1 = "my string"; string string2 = "string"; bool isContained = string1.IndexOf(string2, StringComparison.OrdinalIgnoreCase) >= 0; 

StringComparison.OrdinalIgnoreCase is generally used for more "programmatic" text like paths or constants that you might have generated and is the fastest means of string comparison. For text strings that are linguistic use StringComparison.CurrentCultureIgnoreCase or StringComparison.InvariantCultureIgnoreCase.