CODEWITHSUNDEEP
openlayers
Pari
Pari

Reputation: 339

How filter points in WMS?

I am using WMS as overlay map. I want to filter the point shapefile which is in WMS. Currently using only WMS Code to display in whole. For that following is the code.

var jpl_wms = new OpenLayers.Layer.WMS("Administrative Layer",
                "http://localhost:8080/geoserver/test/wms", 
                {layers: "maharashtra_administrative",transparent: true},{isBaseLayer:false});
                map.addLayer(jpl_wms);

this is point file. I want to pass parameter to restrict the points to be display(i.e point<100). Please help me out if any one know.

Upvotes: 0

Views: 4878

Answers (1)

igorti
igorti

Reputation: 3856

You can restrict points in WMS layer by attaching filter to it. First create filter based on some attribute in your shape file:

var filter = new OpenLayers.Filter.Comparison({
   type: OpenLayers.Filter.Comparison.EQUAL_TO,
   property: "id",
   value: 5
});

That will create filter object. You'll need to parse it to XML string. Following code will do the job:

 var parser = new OpenLayers.Format.Filter.v1_1_0();
 var filterAsXml = parser.write(filter);
 var xml = new OpenLayers.Format.XML();
 var filterAsString = xml.write(filterAsXml);

Now that you have a string you can attach it to your WMS layer:

jpl_wms.params["FILTER"] = filterAsString;

If the layer is already drawn you'll have do call redraw() method in order to apply filter:

jpl_wms.redraw();

Upvotes: 4

Related Questions