Logo

Programming-Idioms

# 133 Case-insensitive string contains
Set boolean ok to true if string word is contained in string s as a substring, even if the case doesn't match, or to false otherwise.
New implementation

Be concise.

Be useful.

All contributions dictatorially edited by webmasters to match personal tastes.

Please do not paste any copyright violating material.

Please try to avoid dependencies to third-party libraries and frameworks.

Other implementations 
#include <algorithm>
#include <cctype>
auto ok = std::search(std::begin(s), std::end(s), std::begin(word), std::end(word),
    [](auto c, auto d){
        return std::tolower(c) == std::tolower(d);
    }
) != std::end(s);
ok = s.Contains(word, StringComparison.CurrentCultureIgnoreCase);
bool ok = s.ToLower().Contains(word.ToLower());
import std.string;
ok = indexOf(word, s, CaseSensitive.no) != -1;
bool ok = s.toUpperCase().contains(word.toUpperCase());
ok = s =~ ~r/#{word}/i
Re = re:compile(Word, [caseless, unicode]),
Ok = re:run(S, Re) =/= nomatch.
 function u_i(string, substr)
  character (len=*), intent(in) :: string, substr
  integer :: i,j, c1, c2, u_i
  u_i = 0
  out: do i=1,len(string)-len(substr)+1
   c1 = iachar(string(i:i))
   if (c1 >= iachar('a') .and. c1 <= iachar('z')) c1 = c1 - 32
   do j=0,len(substr)-2
     c2 = iachar(substr(j+1:j+1))
     if (c2 >= iachar('a') .and. c1 <= iachar('z')) c2 = c2 - 32
     if (c1 /= c2) cycle out
   end do
   u_i = i
   return
 end do out
end function u_i

ok = u_i(string, word) /= 0
import "strings"
lowerS, lowerWord := strings.ToLower(s), strings.ToLower(word)
ok := strings.Contains(lowerS, lowerWord)
import Data.Char (toLower)
import Data.List (isInfixOf)
containsIgnoreCase :: String -> String -> Bool
containsIgnoreCase s word = isInfixOf (map toLower word) (map toLower s)
var lowerS = s.toLowerCase();
var lowerWord = word.toLowerCase();
var ok = lowerS.indexOf(lowerWord) !== -1;
import static java.util.regex.Pattern.compile;
import static java.util.regex.Pattern.quote;
import java.util.regex.Pattern;
Pattern p = compile("(?i)" + quote(word));
boolean ok = p.matcher(s).find();
ok = s.toLowerCase().contains(word.toLowerCase());
local ok=string.find(string.lower(s),string.lower(word),nil,true)~=nil
ok = string.find(string.lower(s), string.lower(word)) and true or false
$ok = stripos($word, $s) === false;
OK := Pos(LowerCase(AWord), LowerCase(S)) > 0;
my $ok = $s =~ /\Q$word/i;
from re import search, escape
p = '(?i)' + escape(word)
ok = not not search(p, s)
ok = word.lower() in s.lower()
ok = s.match?( /#{word}/i )
let ok = s.to_ascii_lowercase().contains(&word.to_ascii_lowercase());
extern crate regex;
use regex::RegexBuilder;
let re =
    RegexBuilder::new(&regex::escape(word))
    .case_insensitive(true)
    .build().unwrap();

let ok = re.is_match(s);
extern crate regex;
use regex::Regex;
let re = Regex::new(&format!("(?i){}", regex::escape(word))).unwrap();
let ok = re.is_match(&s);

Preview