code: function(value, callback, origin){
              var num = 0;
              layui.each(dds, function(){
                var othis = $(this)
                ,text = othis.text()
                ,not = text.indexOf(value) === -1;
                if(value === '' || (origin === 'blur') ? value !== text : not) num++;
                origin === 'keyup' && othis[not ? 'addClass' : 'removeClass'](HIDE);
              });
              var none = num === dds.length;
              return callback(none), none;
            }
docs: 检测值是否不属于 select 项