anchor.diff:          anchor: new BMap.Size(10, 30),
           infoWindowAnchor: new BMap.Size(10, 0)
         });
  -    - if (tolat && tolng)
  +    - if (lat && lng && tolat && tolng)
         script.
           var p1 = new BMap.Point(#{lng}, #{lat});      // where the user is
           var p2 = new BMap.Point(#{tolng}, #{tolat});  // where the store is
           var driving = new BMap.DrivingRoute(map, { renderOptions: { map: map, autoViewport: true} });
           driving.search(p1, p2);
  -    - else
  +    - else if (lat && lng)
         script.
  +        var myCity = new BMap.LocalCity();
  +        myCity.get(function(result){
  +          var cityName = result.name;
  +          map.centerAndZoom(cityName, 11);
  +        });
           var storeInfo = function(name, address, tel, store_lat, store_lng){
             return '<h2 style="margin: 0; padding: 0;">' + name + '</h2>' +
               '<p>地址：' + address + '</p>' +
  
positive.code:           }
          };
        script(src='/api/stores?lat=#{lat}&lng=#{lng}&count=#{count}&callback=stores2points')
  
negative.code:       var map = new BMap.Map("map");
        map.enableScrollWheelZoom();
        map.addControl(new BMap.NavigationControl());
        var icon_green = new BMap.Icon('/images/marker_green.png', new BMap.Size(20, 32), {
          anchor: new BMap.Size(10, 30),
          infoWindowAnchor: new BMap.Size(10, 0)
  