lua dkjson get value from json array - json

local json = require ("dkjson")
local obj = {"dogs":[{"photo":"http://example.com/1.jpg","price":20}]}
obj_t = json.decode(obj)
I'm use construction: obj_t.dogs.photo and this return nil

This is not a valid Lua code, but if we fix the string (local obj = [==[{"dogs":[{"photo":"http://example.com/1.jpg","price":20}]}]==]) then it looks like the problem is that you have a map with an array that has a map in it, so you're missing accessing the array element. You need to use something like obj_t.dogs[1].photo.

Related

Is it possible to iterate over a json object having `\n` and \`` characters in typescript?

I have a json object which is something like below:
"\"{\\n \\\"Foo\\\" : \\\"1234\\\",\\n}\""
Is it somehow possible to iterate through this json object?I tried but my logic did not work which i feel is basically because of these \n and \ i am unable to iterate.How can i get rid of these unnecessary characters ?
The string you've shown is double-encoded JSON if we assume that you've removed some of the content (it has a trailing , in the JSON, which JSON doesn't allow).
If you run it through JSON.parse, you get a string containing JSON for an object.
If you run that through JSON.parse, you get an object.
E.g.:
const parsedOnce = JSON.parse(str);
const obj = JSON.parse(parsedOnce);
Then you loop through that object's properties in the normal way (for-in, Object.keys, Object.entries, etc.).
Live Example:
const str = "\"{\\n \\\"Foo\\\" : \\\"1234\\\"\\n}\"";
const parsedOnce = JSON.parse(str);
const obj = JSON.parse(parsedOnce);
for (const key in obj) {
console.log(`${key} = ${obj[key]}`);
}
That code is also valid TypeScript (playground link), though if you have a type you can apply to obj so it doesn't default to any, that would be good. (You could apply {[key: string]: any} to it at minimum.)

Is there a way to define a to_json handler in GDScript?

I'm new to GDScript and am looking at how best to save data to a text file. to_json works well for basic types but I just get a reference id for any custom classes. I'd ideally like to pass a dictionary of data including some custom class elements to to_json and let it convert it all at once.
Like other languages provide a toString method for printing an object, is there anything that would let me specify how a class instance should be converted to JSON?
Yeah, you would just add something like the following to your class:
func to_json():
var data = {} #must create it as a dictionary or array
data["health"] = 5
#code to create json
var json
json = data.to_json() #dictionaries automatically have this function
return json
I think it really is that simple :)
Please note: I have not tested this code.

Ambiguous format output in nodejs

I am having output in following format as
"[{"a":"a1"},{"a":"a2"}]"
I want to actually extract it in array of json:
[
{
"a":"a1"
},
{
"a":"a2"
}
]
How to convert it?
You have tagged this with Node-RED - so my answer assumes that is the environment you are working in.
If you are passing a message to the Debug node and that is what you see in the Debug sidebar, that indicates your msg.payload is a String with the contents of [{"a":"a1"},{"a":"a2"}] - the Debug sidebar doesn't escape quotes when displaying strings like that.
So you likely already have exactly what you want - it just depends what you want to do with it next.
If you want to access the contents you need to parse it to a JavaScript Object. You can do this by passing your message through a JSON node.
Assuming your input contains the double quotes in the beginning and end, it is not possible to directly JSON.parse() the string.
In your case, you need to remove the first and last character (the double quotes) from your string before parsing it.
const unformattedString = '"[{"a":"a1"},{"a":"a2"}]"'
const formattedString = unformattedString.substr(1, unformattedString.length - 2)
const json = JSON.parse(formattedString)
The variable json now contains your JSON object.
I would suggest a different method which will get your work done without using any third party library.
var a = '[{"a":"a1"},{"a":"a2"}]';
var b = JSON.parse(a);
console.log(b); // b will return [{"a":"a1"},{"a":"a2"}]
Another way which is eval function which is generally not recommended
var d = eval(a);
If you want to use JQuery instead use :
var c = $.parseJSON(a);

trying to convert data from Domino Access Service to a JSON string via JSON.stringify

I want to store the result from a call to a Domino Access Service (DAS) in a localStorage however when I try to convert the result object to a JSON string I get an error.
With DAS you get the result as an Array e.g.:
[
{
"#entryid":"1-CD90722966A36D758025725800726168",
"#noteid":"16B46",
Does anyone know how I get rid of the square brackets or convert the Array quickly to a JSON object?
Here is a snippet of my code:
var REST = "./myREST.xsp/notesView";
$.getJSON(REST,function(data){
if(localStorage){
localStorage.setItem('myCatalog',JSON.stringify(data));
}
});
Brackets are part of the JSON syntax. They indicate that this is an array of objects. And as you point to a view it is very likely that you would get more than one object back (one for each entry in the view).
So if you are only interested in the first element you could do this:
var REST = "./myREST.xsp/notesView";
$.getJSON(REST,function(data){
if(localStorage){
var firstRecord = data[0] || {};
localStorage.setItem('myCatalog',JSON.stringify(firstRecord));
}
});
Otherwise, you would need to define a loop to handle each of the objects :-)
/John

Generate a JSON object form a the value of another JSON in WP8

I am working on a WP8 app. In this I need to connect to web services whose results will be some JSON. I was trying to extract some data from the result that the web service provide. I was able to extract from the initial JSON response. But I need to get some data from the value of one such key . SO I tried to generate another Json object from it. But I m stuck. please help.Please find my example code below(I am using Newtonsoft.JSon).
private void messages_buttons_Click(object sender, RoutedEventArgs e)
{
var str = "{'status': '0', 'result': '%7B%22campaign_id%22%3A%221%22%2C%22tfn%22%3A%2218773374136%22%2C%22campaign_code%22%3A%22PJC%22%2C%22ad_id%22%3A%221%22%2C%22qr_url%22%3A%22http%3A%5C%2F%5C%2F1d1.us%5C%2FPJC%5C%2F%22%2C%22campaign_name%22%3A%22PJ+Test+Campaign%22%2C%22is_active%22%3A%221%22%2C%22expire_on%22%3A%222021-05-05+00%3A00%3A00%22%2C%22start_on%22%3A%222021-05-05+00%3A00%3A00%22%2C%22alias%22%3A%22%22%2C%22icon_image_url%22%3A%22products%5C%2Fpjc%5C%2Fpjc3.jpg%22%2C%22fb_page_url%22%3A%22https%3A%5C%2F%5C%2Fwww.facebook.com%5C%2FJackLaLannePowerJuicerssfb%22%2C%22video_url%22%3A%22http%3A%5C%2F%5C%2Fyoutube.com%5C%2Fembed%5C%2FyZPedpRA9r0%3Fshowinfo%3D0%26autoplay%3D1%26loop%3D1%26playlist%3DyZPedpRA9r0%22%2C%22url%22%3A%22https%3A%5C%2F%5C%2Fwww.facebook.com'}";
JObject ne = JObject.Parse(str);
var x= (ne.GetValue("result")).ToString();
var z = x.Replace("%", "");
JObject newest = JObject.Parse(z);
var y = newest.GetValue("campaign_id");
MessageBox.Show(y.ToString());
}
I get an exception at "JObject newest = JObject.Parse(z);" with the message
Unexpected character encountered while parsing number: m. Path '', line 1, position 6.
Am I doing it entirely wrong?
On a general note: can I convert a value from one Json to a another JSOn Itself? i.e if the value of one json key is a string with some key value pairs, can i make a json object on that string?
You can't actually just remove the % chars to get a valid value. You need to decode the string.
If you use this:
HttpUtility.UrlDecode(x);
You'll find your "result" is actually invalid JSON:
{"campaign_id":"1","tfn":"18773374136","campaign_code":"PJC","ad_id":"1","qr_url":"http://1d1.us/PJC/","campaign_name":"PJ
Test Campaign","is_active":"1","expire_on":"2021-05-05
00:00:00","start_on":"2021-05-05
00:00:00","alias":"","icon_image_url":"products/pjc/pjc3.jpg","fb_page_url":"https://www.facebook.com/JackLaLannePowerJuicerssfb","video_url":"http://youtube.com/embed/yZPedpRA9r0?showinfo=0&autoplay=1&loop=1&playlist=yZPedpRA9r0","url":"https://www.facebook.com
So hacking the value to make it valid JSON might work for you, by adding the missing "} at the end should turn your value in to valid JSON and allow you to parse it.
JObject newest = JObject.Parse(x + "\"}");
var y = newest.GetValue("campaign_id");
It doesn't appear that z is a valid json object at this point. It is only the value of result. Try something like JObject.Parse("'result':" + z);