Proper way to catch exception from JSON.parse
i post something into an iframe then read back the contents of the iframe with json parse...so sometimes it's not a json string
Try this:
if(response) {
try {
a = JSON.parse(response);
} catch(e) {
alert(e); // error in the above string (in this case, yes)!
}
}
We can check error & 404 statusCode, and use try {} catch (err) {}
.
You can try this :
const req = new XMLHttpRequest();
req.onreadystatechange = function() {
if (req.status == 404) {
console.log("404");
return false;
}
if (!(req.readyState == 4 && req.status == 200))
return false;
const json = (function(raw) {
try {
return JSON.parse(raw);
} catch (err) {
return false;
}
})(req.responseText);
if (!json)
return false;
document.body.innerHTML = "Your city : " + json.city + "<br>Your isp : " + json.org;
};
req.open("GET", "https://ipapi.co/json/", true);
req.send();
Read more :
- Catch a 404 error for XHR