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.
Read moreHow do you make a case sensitive?
Both String#includes() and String#indexOf() are case sensitive. Neither function supports regular expressions. To do case insensitive search, you can use regular expressions and the String#match() function , or you can convert both the string and substring to lower case using the String#toLowerCase() function.
Read moreWhat is indexOf () in JavaScript?
indexOf() The indexOf() method, given one argument: a substring to search for, searches the entire calling string, and returns the index of the first occurrence of the specified substring .
Read moreHow do you make indexOf case insensitive?
Yes, it is case-sensitive. You can do a case-insensitive indexOf by converting your String and the String parameter both to upper-case before searching . Note that toUpperCase may not work in some circumstances.
Read moreIs JavaScript case insensitive?
JavaScript is a case-sensitive language . This means that language keywords, variables, function names, and any other identifiers must always be typed with a consistent capitalization of letters.
Read moreHow do you lowercase an array?
To convert all array elements to lowercase:
Read moreIs indexOf case sensitive?
indexOf() methods are all case-sensitive .
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