I'm trying to parse a bit.ly JSON response in javascript.
I get the JSON via XmlHttpRequest.
var req = new XMLHttpRequest;
req.overrideMimeType("application/json");
req.open('GET', BITLY_CREATE_API + encodeURIComponent(url)
+ BITLY_API_LOGIN, true);
var target = this;
req.onload = function() {target.parseJSON(req, url)};
req.send(null);
parseJSON: function(req, url) {
if (req.status == 200) {
var jsonResponse = req.responseJSON;
var bitlyUrl = jsonResponse.results[url].shortUrl;
}
I do this in a firefox addon. When I run I get the error "jsonResponse is undefined" for the line var bitlyUrl = jsonResponse.results[url].shortUrl;
. Am I doing anything wrong in parsing JSON here? Or what is wrong with this code?
This question is related to
javascript
json
firefox-addon
bit.ly
I think you have to include jQuery to use responseJSON
.
Without jQuery, you could try with responseText and try like eval("("+req.responseText+")");
UPDATE:Please read the comment regarding eval
, you can test with eval, but don't use it in working extension.
OR
use json_parse : it does not use eval
You can simply set xhr.responseType = 'json';
const xhr = new XMLHttpRequest();_x000D_
xhr.open('GET', 'https://jsonplaceholder.typicode.com/posts/1');_x000D_
xhr.responseType = 'json';_x000D_
xhr.onload = function(e) {_x000D_
if (this.status == 200) {_x000D_
console.log('response', this.response); // JSON response _x000D_
}_x000D_
};_x000D_
xhr.send();_x000D_
_x000D_
Note: I've only tested this in Chrome.
it adds a prototype function to the XMLHttpRequest .. XHR2,
in XHR 1 you probably just need to replace this.response
with this.responseText
Object.defineProperty(XMLHttpRequest.prototype,'responseJSON',{value:function(){
return JSON.parse(this.response);
},writable:false,enumerable:false});
to return the json in xhr2
xhr.onload=function(){
console.log(this.responseJSON());
}
EDIT
If you plan to use XHR with arraybuffer
or other response types then you have to check if the response is a string
.
in any case you have to add more checks e.g. if it's not able to parse the json.
Object.defineProperty(XMLHttpRequest.prototype,'responseJSON',{value:function(){
return (typeof this.response==='string'?JSON.parse(this.response):this.response);
},writable:false,enumerable:false});
Use nsIJSON if this is for a FF extension:
var req = new XMLHttpRequest;
req.overrideMimeType("application/json");
req.open('GET', BITLY_CREATE_API + encodeURIComponent(url) + BITLY_API_LOGIN, true);
var target = this;
req.onload = function() {target.parseJSON(req, url)};
req.send(null);
parseJSON: function(req, url) {
if (req.status == 200) {
var jsonResponse = Components.classes["@mozilla.org/dom/json;1"]
.createInstance(Components.interfaces.nsIJSON.decode(req.responseText);
var bitlyUrl = jsonResponse.results[url].shortUrl;
}
For a webpage, just use JSON.parse
instead of Components.classes["@mozilla.org/dom/json;1"].createInstance(Components.interfaces.nsIJSON.decode
Source: Stackoverflow.com