Generate a British National Grid reference from a hosted feature layer in AGOL

Question

Morning,

I was wondering if it is possible to use an arcade expression in a pop-up to generate a British National Grid reference in AGOL?

I have been able to do this in ArcGIS Pro in a project which is projected to the British National Grid, calculating geometry attributes for an xy and then using a some python coding to generate a BNG reference from that.

I can also use arcade expressions to show the lat long of a feature in AGOL and or show a BNG reference from an existing xy field in the hosted feature layer.

So is it possible to do this all in AGOL? Take a feature, get the xy and then generate a BNG reference?

I expect that there would be an issue with AGOL using WGS84 Web Mercator (Auxiliary Sphere).

Thanks,

Andy

Lily_A · Answer

Hey Andy,

This is the arcade that we use in FieldMaps to generate a BNG reference for any location within England - I haven't tried it in a pop up, but I don't see why it shouldn't work.

//List of variablesvar Arcadex = round(Geometry($feature).x, 0)var x1 = Text(Arcadex)var countx = count(x1)var initialx = x1[0]
var Arcadey = round(Geometry($feature).y, 0)var y1 = Text(Arcadey)var county = count(y1)var initialy = y1[0]
//evaluate whether northing and easting are equal to 5/6/7 digits //5 digits for preceding zero along south coastvar condX1 = when(countx > 5, number(initialx), 0)var condY1 = when(county == 6, number(initialy), 0)
//combining both conditions (CondX1 + CondY1)var EaNoInit = text(condX1) + text(condY1)
//Calculating BNG grid lettersvar BNGletter = when(EaNoInit == "00", "SV", EaNoInit == "10", "SW",EaNoInit == "20", "SX", EaNoInit == "30", "SY",EaNoInit == "40", "SZ", EaNoInit == "50", "TV",EaNoInit == "60", "TW",EaNoInit == "01", "SQ", EaNoInit == "11", "SR",EaNoInit == "21", "SS", EaNoInit == "31", "ST",EaNoInit == "41", "SU", EaNoInit == "51", "TQ",EaNoInit == "61", "TR",EaNoInit == "02", "SL", EaNoInit == "12", "SM",EaNoInit == "22", "SN", EaNoInit == "32", "SO",EaNoInit == "42", "SP", EaNoInit == "52", "TL",EaNoInit == "62", "TM",EaNoInit == "03", "SF", EaNoInit == "13", "SG",EaNoInit == "23", "SH", EaNoInit == "33", "SJ",EaNoInit == "43", "SK", EaNoInit == "53", "TF",EaNoInit == "63", "TG",EaNoInit == "04", "SA", EaNoInit == "14", "SB",EaNoInit == "24", "SC", EaNoInit == "34", "SD",EaNoInit == "44", "SE", EaNoInit == "54", "TA",EaNoInit == "64", "TB",EaNoInit == "05", "NV", EaNoInit == "15", "NW",EaNoInit == "25", "NX", EaNoInit == "35", "NY",EaNoInit == "45", "NZ", EaNoInit == "55", "OV",EaNoInit == "65", "OW",EaNoInit == "06", "NQ", EaNoInit == "16", "NR",EaNoInit == "26", "NS", EaNoInit == "36", "NT",EaNoInit == "46", "NU", EaNoInit == "56", "OQ",EaNoInit == "66", "OR",EaNoInit == "07", "NL", EaNoInit == "17", "NM",EaNoInit == "27", "NN", EaNoInit == "37", "NO",EaNoInit == "47", "NP", EaNoInit == "57", "OL",EaNoInit == "67", "OM",EaNoInit == "08", "NF", EaNoInit == "18", "NG",EaNoInit == "28", "NH", EaNoInit == "38", "NJ",EaNoInit == "48", "NK", EaNoInit == "58", "OF",EaNoInit == "68", "OG",EaNoInit == "09", "NA", EaNoInit == "19", "NB",EaNoInit == "29", "NC", EaNoInit == "39", "ND",EaNoInit == "49", "NE", EaNoInit == "59", "OA",EaNoInit == "69", "OB","Not valid")
var Easting = left(right(x1, 5), 4)var Northing = left(right(y1, 5), 4)var BNG = BNGletter + " " + easting + " " + northing
return BNG

AndrewHankinson · Answer

@JonathanMcD , thanks very much for offering to do that, very much appreciated. Would the Geometry.x and Geometry.y be calcuated and be taken from an existing field?

JonathanMcD · Answer

@AndrewHankinson

Whilst the grid squares won't give you what you need, they'll at the very least give you the correct grid ID. After than you'd concatenate the Grid ID with the gathered x (easting) and y (northing) coordinates.

In arcade, for the pop-up, you'd take the GRID ID then Geometry.x and Geometry.y to return what you're after.

If I have a moment later today I'll try and put together an example for you and share the map here.