How to convert/query SHAPE.STArea() field value and display in info/pop up window

KushendraShah1 · ‎01-27-2016

Here is my code:

<!DOCTYPE html>

<html>

<head>

<title>Map and Layer</title>

<style>

html, body, #map {

height: 100%;

margin: 0;

}

#info {

position: absolute;

right: 0;

top: 0;

padding: 10px;

background-color: #999;

font: 14px Segoe UI;

width: 200px;

text-align: center;

border-radius: 0 0 0 10px;

}

</style>

var map, calculateAcreage;

require([

"esri/map", "esri/layers/FeatureLayer", "esri/InfoTemplate",

"esri/dijit/Legend",

"esri/Color", "dojo/number", "dojo/domReady!"

], function(

Map, FeatureLayer, InfoTemplate,

Legend,

Color, number

) {

map = new Map("map", {

basemap: "gray",

center: [-97.144, 34.174],

zoom: 6

});

map.on("layers-add-result", createLegend);

var infoTemplate = new InfoTemplate(

"${Name},

"${SHAPE.STArea()} sq.ft is equivalent to ${SHAPE.STArea():calculateAcreage} acres."

);

var layer = new FeatureLayer("http://url", {

infoTemplate: infoTemplate,

outFields: ["*"],

opacity: 0.5

});

// convert squarefeet to acre

calculateAcreage = function(value) {

var squarefeet = (value.hasOwnProperty("attributes")) ? value.attributes.SHAPE.STArea() : value;

return number.format(squarefeet / 43560, { places: 2 });

};

map.addLayers([layer]);

function createLegend(results) {

var legend = new Legend({

layerInfos: [{

layer: results.layers[0].layer,

title: " "

}],

map: map

}, "legend");

legend.startup();

}

});

</script>

</head>

<body>

<div style="font-size: 36px;">Acreage of Cooperator Land.</div>

</div>

</body>

</html>

TomSellsted · ‎01-28-2016

Kushendra,

I couldn't figure out a simple way to access the Shape.STArea() value. It does seem like you should be able to use it directly. Maybe someone else will have a solution.

I do have a workaround for you using the geometryEngine. Call your function from the infoTemplate something like this:

var infoTemplate = new InfoTemplate(
    "${Name}",
    calculateAcreage
);

Add the function:

function calculateAcreage(value) {
    var sqft = geometryEngine.geodesicArea(value.geometry, "square-feet");
    var squarefeet = number.format(sqft, { places: 1 });
    var acres = number.format(sqft / 43560, { places: 2 });
    return squarefeet + " sq.ft is equivalent to " + acres + " acres."
}

I hope this helps!

Regards,

Tom

View solution in original post

TomSellsted · ‎01-28-2016

Kushendra,

I couldn't figure out a simple way to access the Shape.STArea() value. It does seem like you should be able to use it directly. Maybe someone else will have a solution.

I do have a workaround for you using the geometryEngine. Call your function from the infoTemplate something like this:

var infoTemplate = new InfoTemplate(
    "${Name}",
    calculateAcreage
);

Add the function:

function calculateAcreage(value) {
    var sqft = geometryEngine.geodesicArea(value.geometry, "square-feet");
    var squarefeet = number.format(sqft, { places: 1 });
    var acres = number.format(sqft / 43560, { places: 2 });
    return squarefeet + " sq.ft is equivalent to " + acres + " acres."
}

I hope this helps!

Regards,

Tom

KushendraShah1 · ‎01-28-2016

Awesome Tom!. That works great. I didn't realize geometry engine is powerful one. I have been digging out all this morning to fix this issue. Thank you so much for the help!. Truly appreciated!!

TomSellsted · ‎01-28-2016

Kushendra,

You are welcome!

Also note that if you are using a typical ArcGIS basemaps, then geodesicArea is correct. If the basemap you are using is for instance in stateplane coordinates, you should use planarArea.

esri/geometry/geometryEngine | API Reference | ArcGIS API for JavaScript

The first paragraph in this link gives a good explanation of which to use.

Best Regards,

Tom

KushendraShah1 · ‎01-29-2016

Thanks for the insights Tom.

JordanBaumgardner · ‎01-29-2016

MS SQL has Geometry functions that might be helpful if you didn't want to preform the calc on the client side.

Select shape.STArea() as Area from sde.COUNTIES

KushendraShah1 · ‎02-01-2016

Thanks Jordan.