js将foo-bar转为fooBar

这是一道js的面试题,就是考察将普通面命转为小驼峰命名

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
</head>
<body>
    
</body>
<script type="text/javascript">
    function fooBar(str) {
        var arr = [];
        let sting = str.split('-');
        arr.push(sting[0]);
        for (var i = 1; i < sting.length; i ++) {
            arr.push(sting[i].toString()[0].toUpperCase() + sting[i].toString().slice(1));
        }
        return arr.join('');
    }
    document.write(fooBar('foo-bar'));
</script>
</html>