Search code examples
javascriptjqueryarrayscontainscase-insensitive

JS - jQuery inarray ignoreCase() and contains()


well, I am more of a PHP person, and my JS skills are close to none when it comes to any JS other than simple design related operations , so excuse me if I am asking the obvious .

the following operations would be a breeze in PHP (and might also be in JS - but I am fighting with unfamiliar syntax here ...)

It is some sort of input validation

var ar = ["BRS201103-0783-CT-S", "MAGIC WORD", "magic", "Words", "Magic-Word"];

    jQuery(document).ready(function() {
        jQuery("form#searchreport").submit(function() {
        if (jQuery.inArray(jQuery("input:first").val(), ar) != -1){ 
                jQuery("#contentresults").delay(800).show("slow");

            return false;
          }

This question has 2 parts .

  • 1 - how can I make it possible for the array to be case insensitive ?

E.g. - BRS201103-0783-CT-S will give the same result as brs201103-0783-ct-s AND Brs201103-0783-CT-s or MAGIC magic Magic MaGIc

basically i need something like ignoreCase() for array , but I could not find any reference to that in jQuery nor JS...

I tried toLowerCase() - but It is not working on the array (ittirating??) and also, would it resolve the mixed case ?

  • 2 - How can I make the function to recognize only parts or combinations of the elements ?

E.g. - if one types only "word" , I would like it to pass as "words" , and also if someone types "some word" it should pass (containing "word" )


Solution

  • Part 1

    You can process your array to be entirely lowercase, and lowercase your input so indexOf() will work like it's performing a case insensitive search.

    You can lowercase a string with toLowerCase() as you've already figured out.

    To do an array, you can use...

    arr = arr.map(function(elem) { return elem.toLowerCase(); }); 
    

    Part 2

    You could check for a substring, for example...

    // Assuming you've already transformed the input and array to lowercase.
    var input = "word";
    var words = ["word", "words", "wordly", "not"];
    
    var found = words.some(function(elem) { return elem.indexOf(input) != -1; });
    

    Alternatively, you could skip in this instance transforming the array to be all lowercase by calling toLowerCase() on each elem before you check indexOf().

    some() and map() aren't supported in older IEs, but are trivial to polyfill. An example of a polyfill for each is available at the linked documentation.

    As Fabrício Matté also pointed out, you can use the jQuery equivalents here, $.map() for Array.prototype.map() and $.grep() with length property for Array.prototype.some(). Then you will get the browser compatibility for free.