JavaScript RegExp to CamelCase a hyphened CSS property

Another, slightly more flexible answer:

if (typeof String.prototype.toCamel !== 'function') {
  String.prototype.toCamel = function(){
    return this.replace(/[-_]([a-z])/g, function (g) { return g[1].toUpperCase(); })
  };
}

Used like this:

'-moz-border-radius'.toCamel(); // "MozBorderRadius"
'moz-border-radius'.toCamel(); // "mozBorderRadius"
'moz_border_radius'.toCamel(); // "mozBorderRadius"
'_moz_border_radius'.toCamel(); // "MozBorderRadius"

You would be better off using a function as the second parameter in replace(), and you could also use a regex literal instead of the RegExp constructor:

var replaced = '-moz-border-radius'.replace(/-([a-z])/gi, function(s, group1) {
    return group1.toUpperCase();
});

You need to pass a callback function instead of a string.

For example:

var exp = /-([a-z])/gi;
console.log('-moz-border-radius'.replace(exp, 
    function(match, char, index, str) {
        return char.toUpperCase();
    }
));