topic Re: Is it possible to merge line features with the Javascript API? in ArcGIS JavaScript Maps SDK Questions

Is it possible to merge line features with the Javascript API?

SteveClarke — Mon, 05 May 2014 18:41:56 GMT

Has anyone been able to successfully merge two or more line geometries with the JAPI? If so, is there sample code somewhere? The editor widget in the api provides a union tool but that only works for polygons. Interestingly, the doc for the editor widget calls this operation a merge and not a union, but it is just a union of polygons. That's a bit confusing since there is a difference between a merge and union operation. And according to the doc, the geometry service only allows for a union and not a merge like you can do in ArcMap. I'm trying to create a web app that will allow my editors to merge line features. The following older post asked a similar question but it was never answered.

http://forums.arcgis.com/threads/47155-Editor-Widget-Union-Tool-and-Polyline-features?highlight=merge+polyline+javascript

I would appreciate any insight as to how to do this with JAPI.

Re: Is it possible to merge line features with the Javascript API?

BrandonFlessner — Fri, 10 Dec 2021 23:11:16 GMT

I haven't explored using the editor widget but here is a code sample that should get you started:

function mergeLines(graphicsArray) {
     // merge geometries of polyline graphics into one geometry (graphics array could be map.graphics.graphics, featureLayer.graphics, etc.)
     var polyline = new Polyline(map.spatialReference);
     for (var i = 0; i < graphics.length; i++){
          var paths = graphics.geometry.paths;
          for (var j = 0; j < paths.length; j++){ //needed for multi part lines
          polyline.addPath(paths);
          }
     }
    return polyline;
}
  
var mergedGraphicGeometry = mergeLines();

Re: Is it possible to merge line features with the Javascript API?

AndrzejBieniek — Mon, 12 Dec 2016 17:21:30 GMT

If you have your own API deployed on your server go to the file (https://js.arcgis.com/3.18/esri/dijit/editing/Editor.js) and find:

function(a){return"esriGeometryPolygon"===a.geometryType&&a.visible&&a._isMapAtVisibleScale()}

To fix the bug with merging the above must be replaced with:

function(a){return a.geometryType&&a.visible&&a._isMapAtVisibleScale()}

For some reason Esri is checking if the geometry type is polygon before UNION function is used on the geometry server? WHY???

Removed "esriGeometryPolygon"===a.geometryType

Everything working as expected.

Hope this helps.

Regards,

Andrzej