How do you use indexOf case insensitive?

You can’t make . indexOf() case insensitive. You can normalize the case between the Array and the search term. You seem to be doing a search and then converting the case, so that isn’t going to help you.

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The indexOf() method returns the index number where the target string is first found or -1 if the target is not found. Like equals(), the indexOf() method is case-sensitive , so uppercase and lowercase chars are considered to be different.

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