JavaScript 回车键转成Tab键

 var inputs = $("#tb_Content input");
    $("#tb_Content input").keydown(function (event) {
        if("[13][38][40]".indexOf("["+event.keyCode+"]")>-1){ if (event.target.type == "submit" && event.keyCode == 13)
                return;
            var index = 0;
            for (; index < inputs.length; index++)
                if ($(inputs[index]).attr("id") == event.target.id)
                    break;
            switch (event.keyCode) {
                case 13: //回车键
                case 40: //下 
                    index++;
                    break;
                case 38: //上   
                    index--;
                    break;
            }
            if (index == inputs.length)
                index = 0;
            if (index < 0)
                index = inputs.length - 1;
            $(inputs[index]).focus();
            return false;
        }
    });