camelcase.js

function camelcase (str) {
     var arr;
     if (str.length === 0) {
         return;
     }
     arr = str.split('-');
     if (arr.length === 1) {
         arr = str.split(' ');
     }
     if (arr.length === 1) {
         return str;
     }
     return (arr.map(function (elm, i) {
         if (i > 0) {
             return elm[0].toUpperCase() + elm.slice(1);
         } else {
             return elm;
         }
     })).join('');
}