Question

I’m trying to get a case-insensitive search with two strings in JavaScript working.

Normally it would be like this:

var string='Stackoverflow is the BEST'; var result= string.search(/best/i); alert(result); 

The /i flag would be for case-insensitive.

But I need to search for a second string; without the flag it works perfect:

var string='Stackoverflow is the BEST'; var searchstring='best'; var result= string.search(searchstring); alert(result); 

If I add the /i flag to the above example it would search for searchstring and not for what is in the variable ‘searchstring’ (next example not working):

var string='Stackoverflow is the BEST'; var searchstring='best'; var result= string.search(/searchstring/i); alert(result); 

How can I achieve this?

Answer 1

Yeah, use .match, rather than .search. The result from the .match call will return the actual string that was matched itself, but it can still be used as a boolean value.

var string = 'Stackoverflow is the BEST'; var result = string.match(/best/i); // result == 'BEST';  if (result){     alert('Matched'); } 

Using a regular expression like that is probably the tidiest and most obvious way to do that in JavaScript, but bear in mind it is a regular expression, and thus can contain regex metacharacters. If you want to take the string from elsewhere (eg, user input), or if you want to avoid having to escape a lot of metacharacters, then you’re probably best using indexOf like this:

matchString = 'best'; // If the match string is coming from user input you could do // matchString = userInput.toLowerCase() here.  if (string.toLowerCase().indexOf(matchString) != -1){     alert('Matched'); }