I have a fn that creates and populate variable linkedinInsight when its invoked.
Just a quick overview of this fn, it will check the response data and see if there is a match. If yes, it would populate the linkedinInight variable with the data.
Using Ternary operation, I am unable to display "undefined" when the variable is undefined.
linkedinInsight === undefined ? "undefined" : "Variable exist"
However, if the fn gets a match, I could see "Variable exist" displayed.
In the case where variable is undefined,
from the console, it is showing
Error handling response: TypeError: Cannot read properties of undefined (reading 'insight_tags')
at chrome-extension://fpncfpgjnkfnlafmojhhpgophpgikaao/popup.js:13:60
The objective here is to present the data and if we couldnt find data, I would like to return a "Data not found message".
Any help guys?
document.addEventListener(
"DOMContentLoaded",
function () {
var checkPageButton = document.getElementById("clickIt");
checkPageButton.addEventListener(
"click",
function () {
chrome.tabs.getSelected(null, function (tab) {
const backgroundPage = chrome.extension.getBackgroundPage();
const linkedinInsight =
backgroundPage["_linkedin_pixel_data"][tab.id].insight_tags;
alert(
linkedinInsight === undefined ? "undefined" : "Variable exist"
);
The issue is in below line, replace
const linkedinInsight =
backgroundPage["_linkedin_pixel_data"][tab.id].insight_tags;
with
const linkedinInsight =
(backgroundPage && backgroundPage["_linkedin_pixel_data"] && backgroundPage["_linkedin_pixel_data"][tab.id] && backgroundPage["_linkedin_pixel_data"][tab.id].insight_tags) || undefined;
Or if optional chaining is supported
const linkedinInsight =
backgroundPage?.["_linkedin_pixel_data"]?.[tab.id]?.insight_tags;
Use a nullish coalescingm operator
let exists = value ?? `${value} doesn't exist`;
If the value is undefined or null then return the value on the right side of operator ??
function check(X) {
let present = X ?? `"X" does not exist`;
let limit = X < 10 && X > 0 ? `"X" is within range` : `"X" is out of range`;
if (typeof present == 'string') {
console.log(present);
return;
}
console.log(limit);
}
check(5);
check(10);
check(-1);
check();
check(null);