pulldata @layer for rasters

AMur — Thu, 21 Aug 2025 02:19:15 GMT

Hello,

In Survey123 I am trying to query a DEM raster layer from map lick or coordinates with pulldata @layer but cannot find how to read the stretch.pixel value. Under the layer's service page, Fields is None so not sure what to put in for "attributes"

Re: pulldata @layer for rasters

ChristopherCounsell — Thu, 21 Aug 2025 08:15:58 GMT

Survey123 pulldata(@"layer" is for feature layers, feature tables or query enabled map services.

https://doc.arcgis.com/en/survey123/desktop/create-surveys/xlsformformulas.htm#ESRI_SECTION1_BB97985CAFB740EE8AEF99EFD6E238E3

You may be able to achieve this with JavaScript e.g. here's a starting point:

https://community.esri.com/t5/arcgis-survey123-questions/survey123-javascript-extension-identify-pixel/td-p/779967

Re: pulldata @layer for rasters

Neal_t_k — Thu, 21 Aug 2025 13:00:47 GMT

How big is your area of interest and what level of detail do you need the results? I know DEMs are large when converted to vector even larger, but if you had a small are of interest and could generalize the DEM a bit, you could convert it to a polygon layer and the use the point in polygon pulldata method.

Re: pulldata @layer for rasters

AMur — Sun, 24 Aug 2025 22:57:57 GMT

I have tried to use javascript to perform the action but am running in to issues with the returned json. I am connected through an Enterprise account but if I use the parent url the below script returns the error 'Token Required'. The error in Survey123 is always the same. I can use a child layer and paste the identify url in a browser but it will only return the layer attributes, never the value of the coordinates.

This script creates the following url (I have removed the url and lat/lon info)

<url>/identify?geometry=%7B"x"%3A<lon>%2C"y"%3A<lat>%2C"spatialReference"%3A%7B"wkid"%3A4326%7D%7D&geometryType=esriGeometryPoint&returnGeometry=false&returnCatalogItems=false&f=json

// rasterPixelValue.js
// Call from XLSForm: pulldata("@javascript", "rasterPixelValue.js", "getRasterValue", imageServiceUrl, longitude, latitude)

function getRasterValue(imageServiceUrl, longitude, latitude) {
// Validate inputs
if (!imageServiceUrl || !longitude || !latitude) {
return "Error: Missing required parameters (imageServiceUrl, longitude, latitude)";
}

// Convert coordinates to numbers
const lon = parseFloat(longitude);
const lat = parseFloat(latitude);

if (isNaN(lon) || isNaN(lat)) {
return "Error: Invalid coordinates";
}

try {
// Build the identify request URL
const identifyUrl = imageServiceUrl.endsWith('/')
? imageServiceUrl + 'identify'
: imageServiceUrl + '/identify';

// Create the geometry parameter
const geometry = JSON.stringify({
x: lon,
y: lat,
spatialReference: { wkid: 4326 }
});

// Build request parameters manually
const params = [
'geometry=' + encodeURIComponent(geometry),
'geometryType=esriGeometryPoint',
'returnGeometry=false',
'returnCatalogItems=false',
'f=json'
];

const requestUrl = identifyUrl + '?' + params.join('&');

// Make synchronous request (required for Survey123 pulldata functions)
const xhr = new XMLHttpRequest();
xhr.open('GET', requestUrl, false); // false = synchronous
xhr.withCredentials = true;
xhr.send();

if (xhr.status === 200) {
const response = JSON.parse(xhr.responseText);

// Check for errors in response
if (response.error) {
return "Error: " + response.error.message + " " +requestUrl;
}

// Extract pixel value
let pixelValue = null;

if (response.value !== undefined && response.value !== null) {
pixelValue = response.value;
} else if (response.values && response.values.length > 0) {
// For multi-band rasters, return first band or comma-separated values
pixelValue = response.values.length === 1 ? response.values[0] : response.values.join(',');
} else if (response.properties && Object.keys(response.properties).length > 0) {
// Sometimes pixel data is in properties
const keys = Object.keys(response.properties);
pixelValue = response.properties[keys[0]]; // Return first property value
}

// Return the pixel value or "No Data" if null/undefined
return pixelValue !== null && pixelValue !== undefined ? pixelValue.toString() : "No Data";

} else {
return "Error: HTTP " + xhr.status + " - Unable to query image service";
}

} catch (error) {
return "Error: " + error.message;
}
}

topic pulldata @layer for rasters in ArcGIS Survey123 Questions

pulldata @layer for rasters

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Re: pulldata @layer for rasters

Re: pulldata @layer for rasters