js判断两字符串是否相等不区分大小写

    <script>
        String.prototype.compare = function(str) {
            //不区分大小写
            if(this.toLowerCase() == str.toLowerCase()) {
                return true;
            } else {
                return false;
            }
        }
        alert("ABCDefg".compare("abcdEFG"));
        alert("abc".compare("acd"));
    </script>