Hi -
I am hoping to add some functionality into my XLSForm that would prevent data entry if a duplicate Project ID is entered into Survey123. I would like this to happen as soon as the user enters a Project ID into the form as the form is quite long (it would really stink to get to the end and then see this error!).
I feel like a JavaScript function would be the best method for doing this, however I am struggling to find an example and really do not know how to write one myself.
I do not think pulldata() would be a reasonable solution for this as it would be extremely cumbersome to maintain the external CSV - new projects are being entered weekly. The ideal solution would be a way to look back at the hosted feature service, check the field and see if the Project ID already exists.
I am also wondering if the "Unique" setting could be used to accomplish this; I suspect that it would not cause error until going to submit the survey form.
Any advice would be welcome!
Thank you,
Accepted Solutions
I was able to get some help and figure out how to do this. I wanted to post the result here in case it is helpful to others.
I am using a custom JavaScript function and a series of hidden and relevant questions in the XLSForm to accomplish my goal - prevent the submission of a new Survey123 form if the file number entered is a duplicate value.
First, here is the JS function:
/*
* JavaScript functions for Survey123
*/
function returnFeatures(DCR_File_Number, token, debugmode) {
// Output value. Initially set to an empty string (XLSForm null)
let outValue = "";
let layerURL = "https://URL GOES HERE/FeatureServer/0";
let response ="";
// Set up query parameters
let f = "f=json";
let where = `where=DCR_File_Number='${DCR_File_Number}'`;
let outFields = "outFields=*";
let returnGeometry = "returnGeometry=false";
let returnCount = "returnCount=1";
let parameters = [f,where,outFields,returnGeometry,returnCount].join("&");
let url = `${layerURL}/query?${parameters}`;
if (token){
url = url + "&token=" + token;
}
// Create the request object
let xhr = new XMLHttpRequest();
// Make the request. Note the 3rd parameter, which makes this a synchronous request
xhr.open("GET", url, false);
xhr.send();
// Process the result
if (xhr.readyState === xhr.DONE) {
if (xhr.status !== 200) {
// The http request did not succeed
return "bad request: " + url
} else {
// Parse the response into an object
response = JSON.parse(xhr.responseText);
if (response.error) {
return (debugmode? JSON.stringify(response.error):"");
} else {
if (response.features[0]) {
return "DCR File number is not unique"
//JSON.stringify(response.features[0]);
} else {
if (DCR_File_Number !== "") {
return "DCR File number is unique"}
//(debugmode? "No Features Found":"");
}
}
}
}
}
Next, I configured the XLSForm - here is what all of the populated columns look like (I hid all of the empty/non-relevant columns to fit this into one image):
When the user goes to enter a file number, if it is invalid (AKA a duplicate), they will see this message in the Survey123 form:
Because of line 6 in the XLSForm, they are prevented from submitting their form until they correct the DCR File Number so that it is unique.
When a unique DCR File Number is entered, this message appears and the user is able to submit:
This seems to work very well for my use case. Since this is a web-only form (users only complete from a desktop PC) this works perfectly.
I was able to get some help and figure out how to do this. I wanted to post the result here in case it is helpful to others.
I am using a custom JavaScript function and a series of hidden and relevant questions in the XLSForm to accomplish my goal - prevent the submission of a new Survey123 form if the file number entered is a duplicate value.
First, here is the JS function:
/*
* JavaScript functions for Survey123
*/
function returnFeatures(DCR_File_Number, token, debugmode) {
// Output value. Initially set to an empty string (XLSForm null)
let outValue = "";
let layerURL = "https://URL GOES HERE/FeatureServer/0";
let response ="";
// Set up query parameters
let f = "f=json";
let where = `where=DCR_File_Number='${DCR_File_Number}'`;
let outFields = "outFields=*";
let returnGeometry = "returnGeometry=false";
let returnCount = "returnCount=1";
let parameters = [f,where,outFields,returnGeometry,returnCount].join("&");
let url = `${layerURL}/query?${parameters}`;
if (token){
url = url + "&token=" + token;
}
// Create the request object
let xhr = new XMLHttpRequest();
// Make the request. Note the 3rd parameter, which makes this a synchronous request
xhr.open("GET", url, false);
xhr.send();
// Process the result
if (xhr.readyState === xhr.DONE) {
if (xhr.status !== 200) {
// The http request did not succeed
return "bad request: " + url
} else {
// Parse the response into an object
response = JSON.parse(xhr.responseText);
if (response.error) {
return (debugmode? JSON.stringify(response.error):"");
} else {
if (response.features[0]) {
return "DCR File number is not unique"
//JSON.stringify(response.features[0]);
} else {
if (DCR_File_Number !== "") {
return "DCR File number is unique"}
//(debugmode? "No Features Found":"");
}
}
}
}
}
Next, I configured the XLSForm - here is what all of the populated columns look like (I hid all of the empty/non-relevant columns to fit this into one image):
When the user goes to enter a file number, if it is invalid (AKA a duplicate), they will see this message in the Survey123 form:
Because of line 6 in the XLSForm, they are prevented from submitting their form until they correct the DCR File Number so that it is unique.
When a unique DCR File Number is entered, this message appears and the user is able to submit:
This seems to work very well for my use case. Since this is a web-only form (users only complete from a desktop PC) this works perfectly.
