How to remove L.rectangle(boxes[i]) - leaflet

Question

I few days ago I implement a routingControl = L.Routing.control({...}) which works perfect for my needs. However I need for one of my customer also the RouteBoxer which I was also able to implement it. Now following my code I wants to remove the boxes from my map in order to draw new ones. However after 2 days trying to find a solution I've given up.
wideroad is a param that comes from a dropdown list 10,20,30 km etc.
function routeBoxer(wideroad) {
this.route = [];
this.waypoints = []; //Array for drawBoxes
this.wideroad = parseInt(wideroad); //Distance in km
this.routeArray = routingControl.getWaypoints();
for (var i=0; i<routeArray.length; i++) {
waypoints.push(routeArray[i].latLng.lng + ',' + routeArray[i].latLng.lat);
}
this.route = loadRoute(waypoints, this.drawRoute);
}; //End routeBoxer()
drawroute = function (route) {
route = new L.Polyline(L.PolylineUtil.decode(route)); // OSRM polyline decoding
boxes = L.RouteBoxer.box(route, this.wideroad);
var bounds = new L.LatLngBounds([]);
for (var i = 0; i < boxes.length; i++) {
**L.rectangle(boxes[i], {color: "#ff7800", weight: 1}).addTo(this.map);**
bounds.extend(boxes[i]);
}
console.log('drawRoute:',boxes);
this.map.fitBounds(bounds);
return route;
}; //End drawRoute()
loadRoute = function (waypoints) {
var url = '//router.project-osrm.org/route/v1/driving/';
var _this = this;
url += waypoints.join(';');
var jqxhr = $.ajax({
url: url,
data: {
overview: 'full',
steps: false,
//compression: false,
alternatives: false
},
dataType: 'json'
})
.done(function(data) {
_this.drawRoute(data.routes[0].geometry);
//console.log("loadRoute.done:",data);
})
.fail(function(data) {
//console.log("loadRoute.fail:",data);
});
}; //End loadRoute()
Well, my problem is now how to remove previously drawn boxes in order to draw new ones because of changing the wideroad using a dropdown list. Most of this code I got from the leaflet-routeboxer application.
Thanks in advance for your help...

Answer 1

You have to keep a reference to the rectangles so you can manipulate them (remove them) later. Note that neither Leaflet nor Leaflet-routeboxer will do this for you.
e.g.:
if (this._currentlyDisplayedRectangles) {
for (var i = 0; i < this._currentlyDisplayedRectangles.length; i++) {
this._currentlyDisplayedRectangles[i].remove();
}
} else {
this._currentlyDisplayedRectangles = [];
}
for (var i = 0; i < boxes.length; i++) {
var displayedRectangle = L.rectangle(boxes[i], {color: "#ff7800", weight: 1}).addTo(this.map);
bounds.extend(boxes[i]);
this._currentlyDisplayedRectangles.push(displayedRectangle);
}
If you don't store a reference to the L.rectangle() instance, you obviously won't be able to manipulate it later. This applies to other Leaflet layers as well - not storing explicit references to Leaflet layers is a usual pattern in Leaflet examples.