java script index Of not case senstive

Question

I have this code:

var textarea = document.getElementById('myTextarea');
var tag = '<!DOCTYPE html>';
var textValue = textarea.value;

if (textValue.indexOf(tag) != -1) {
  document.getElementById('status').innerHTML = "match found";
} else {
  document.getElementById('status').innerHTML = "no match found";
}

I’m trying to get indexOf to match tag no matter if the var tag is in upper-case or lower-case. How can I go about doing this?

How about putting your `tag` variable and your `textValue` variable to lower case before comparing them ? — kaycee, May 04 '17 at 19:00
Convert all the content to either lowecase or uppercase and keep the same case for search string also. something like textValue.toUpperCase().indexOf(tag.toUpperCase()) !=-1 — Ananthaprakash, May 04 '17 at 19:02

score 2 · Accepted Answer · answered May 04 '17 at 19:02

2

use toUpperCase() like this

var textarea = document.getElementById('myTextarea');
var tag = '<!DOCTYPE html>';  
var textValue=textarea.value;

if (textValue.toUpperCase().indexOf(tag.toUpperCase())!=-1)
{
   document.getElementById('status').innerHTML = "match found";
} else {
       document.getElementById('status').innerHTML = "no match found";
}

This way the condition compares both as upper case even if one of them is lower case, hence case insensitive

answered May 04 '17 at 19:02

Mostafa El-Messiry

380
1
14

thank you this has work perfectly – Mayhem Of Ben May 04 '17 at 19:23
You're Welcome :) – Mostafa El-Messiry May 04 '17 at 19:24

java script index Of not case senstive

1 Answers1