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v 1.9.45

Run Expression Trigger


function setOfficialCountryName(params) {
    if (params.length < 2)
    var country = params[0];
    var officialName = params[1];
    var survey = this.survey;
    if (!country || !country.length) {
    survey.setVariable("request_processing", true);
    survey.setVariable("request_error", null);
    country = country
        .toUpperCase() + country
        url: "" + country,
        type: "GET",
        success: function (data) {
            if (!!data && data.length > 0) {
                var countryValue = data[0];
                survey.setValue(officialName, countryValue.officialName);
                survey.setVariable("hasError", false);
            } else {
                survey.setVariable("hasError", true);
                survey.setVariable("request_error", "The country is not found.");
                survey.setVariable("request_processing", false);
        error: function (xhr, ajaxOptions, thrownError) {
            survey.setVariable("hasError", true);
            survey.setVariable("request_error", "The country is not found.");

Survey.FunctionFactory.Instance.register("setOfficialCountryName", setOfficialCountryName);

                    var json = {
  "elements": [
      "type": "text",
      "name": "country",
      "title": "Please enter the country"
      "type": "html",
      "name": "requesting",
      "html": "The data is requesting",
      "visibleIf": "{request_processing} = true"
      "type": "text",
      "name": "name_official",
      "title": "Official name is:",
      "readOnly": true,
      "visibleIf": "{name_official} notempty"
      "type": "html",
      "name": "error",
      "html": "The following error has happened: <b>{request_error}</b>",
      "visibleIf": "{hasError} = true"
  "triggers": [
      "type": "runexpression",
      "expression": "{country} notempty or {country} empty",
      "runExpression": "setOfficialCountryName({country}, 'name_official')"

                    window.survey = new Survey.Model(json);
            survey.onComplete.add(function(sender) {
            document.querySelector('#surveyResult').textContent =
            "Result JSON:\n" + JSON.stringify(, null, 3);

<!DOCTYPE html>
<html lang="en">
    <title>Run Expression Trigger, Knockoutjs Survey Library Example</title>
<meta name="viewport" content="width=device-width" />
    <script src=""></script>
    <script src=""></script>
    <script src="/DevBuilds/survey-core/survey.core.min.js"></script>
    <script src="/DevBuilds/survey-core/survey.i18n.min.js"></script>
    <script src="/DevBuilds/survey-knockout-ui/survey-knockout-ui.min.js"></script>
    <link href="/DevBuilds/survey-core/survey.min.css" type="text/css" rel="stylesheet" />
    <link rel="stylesheet" href="./index.css">

<body style="margin: 0">
            <div id="surveyElement" style="display:inline-block;width:100%;">
    <div id="surveyResult"></div>

<script type="text/javascript" src="./index.js"></script>


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