Javascript replace() with case-change

Question

Is there an easy way to change the case of a matched string with javascript?

Example

String :

something

<

Answer 1

easiest is probably to use a regex match and then use .toUpperCase on the match. I modified the regex slightly to add in a second capture group

var str = '
something
';
var arr = /<([\w]+)([^>]*>.*?<\/)\1>/.exec(str);
str = '<' + arr[1].toUpperCase() + arr[2] + arr[1].toUpperCase() + '>';