How to replace characters in a string with other characters?

Question

I want to replace certain characters in a string with other characters. I´ve did my research and found that the best way is to use regular expressions... But, something does

Answer 1

Match any of those characters using [], and capture the match(es) using () instead of looking for a match of those consecutive characters.

var url = word.replace(/[áéí]/g, function(s) {
    return alphabet[s];
});

DEMO: http://jsfiddle.net/5UmLV/1/

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As noted by @Felix Kling the capture group was unnecessary. Updated to reflect that improvement.