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javascriptregexp-replace

Javascript replace a capture group to uppercase (not a duplicate)

I am aware of Replace a Regex capture group with uppercase in Javascript

That is for replacing the entire match and not a () match.

Here is my problem:

var text = '<span style="font-variant: small-caps" class="small-caps">Lord</span>'
text = text.replaceAll(/<span style="font-variant.*?>(.*)<\/span>/g, function (v) { return v.toUpperCase(); });
console.log(text);

This returns the entire tag as uppercase and not the actual text in (.*).

I just want to replace the span tag with just the uppercase of the innertext. There is more than one span tag as well in the actual text variable.

Solution

  • Capture groups are passed as additional arguments to the callback function. So use the argument with the capture.

    var text = '<span style="font-variant: small-caps" class="small-caps">Lord</span>'
text = text.replaceAll(/<span style="font-variant.*?>(.*)<\/span>/g,
  (match, g1) => g1.toUpperCase());
console.log(text);