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JavaScript Stringify() applies different rules to the key on the same object [duplicate]

This question already has answers here:
JSON.stringify: how to skip indentation for one (or more) objects
(1 answer)
Json - stringify so that arrays are on one line
(10 answers)
JSON.stringify custom formatting
(3 answers)
Closed 3 months ago.
I am working on a JSON file generator while everything works fine the final result is not as good as expected
With following stringify function call, following json file would be generated.
var jsonString = JSON.stringify(object, null, 2);
{
"key_1": 2397,
"key_2": "text1",
"key_3": "text",
"key_4": [
"12345",
"23456"
],
"key_5": [
0,
1
],
"key_6": [
0
],
"key_7": [
"https://xxxx",
"https://xxxx"
],
"key_8": "12345",
}
In the JSON file I want to make key_5 and key_6 skip the stringify attributes and make it like this
"key_5": [0,1],
"key_6": [0],
So the final file would look like this
{
"key_1": 2397,
"key_2": "text1",
"key_3": "text",
"key_4": [
"12345",
"23456"
],
"key_5": [0,1],
"key_6": [0],
"key_7": [
"https://xxxx",
"https://xxxx"
],
"key_8": "12345",
}
I think it is possible to customized the rule for certain key but I am very new to JS so I am not sure how to do so...
jsonString = JSON.stringify(object, (key, value) => {
if (key === "key_5"||key === "key_6") return Do_something_ELSE;
return value;
}, 2);

how can I retrieve specific property of an object of multiple objects [duplicate]

This question already has answers here:
Perform .join on value in array of objects
(14 answers)
Closed 1 year ago.
I need help in getting values of specific property of an array of multiple objects
I have an array like this:
[
{
"id": 1,
"name": "skill 1"
},
{
"id": 2,
"name": "skill 2"
},
{
"id": 3,
"name": "skill 3"
}]
and I want to get a string like this :
skill 1 - skill 2 - skill 3

First step is to extract name. You can use map.
elements.map(x=>x.name)
Second step is to join it to one string using join
const result = elements.map(x=>x.name).join(' - ');

How to efficiently remove nameless attribute from json object js [duplicate]

This question already has answers here:
How do I remove all null and empty string values from an object? [duplicate]
(13 answers)
Closed 1 year ago.
I have a very large array of objects and some of the objects have a nameless property. What is an efficient way to remove the property?
[
...
{
"phone_number": "***-***-****",
"category": "Abc",
"link_to_company": "www.example.com",
"email": "test#test.com",
"company_name": "test company",
"": "123", // this need to be removed
"status": 1
},
...
]

A map function should do it.
array.map(v => { delete v[""]; return v })

Why Json.parse keeps changing my interger value in a nested object [duplicate]

This question already has answers here:
What is JavaScript's highest integer value that a number can go to without losing precision?
(21 answers)
Closed 6 years ago.
my obj = {
"formname": ["appname", {
"operation": ["add", {
"values": {
"Activation_code": "12345",
"ID": 722756000010586033,
"game_Id": "10000"
},
"status": "Success"
}]
}]
}
The above code is my object from a server I have no problem getting the value the point am making is why JSON.parse(obj) is changing the ID after the object as gone through its function.
hence after a parse it spits back the ID as 722756000010586000 Why?

Cos of number precision, your id is way past max safe integer, I suggest keeping it as string.
console.log(722756000010586033 > Number.MAX_SAFE_INTEGER)
console.log(722756000010586033);
Basically there is some finite memory used to store numbers in JS and with finite momory comes finite number of digits that can be remember. This is ofc a little bit more complicated than that, but that is basically it.
You can extract your id with regular expression:
const JSON = `{
"formname": ["appname", {
"operation": ["add", {
"values": {
"Activation_code": "12345",
"ID": 722756000010586033,
"game_Id": "10000"
},
"status": "Success"
}]
}]
}`;
const matched = JSON.match(/"ID":\s*(\d+),/);
const id = matched[1];
document.body.innerHTML = id;

How to get last item from array of object? [duplicate]

This question already has answers here:
Get the last item in an array
(59 answers)
Closed 6 years ago.
I have JSON object from server and requirement is to always display last item from the array items. how can i achieve that task using AngularJs or native JavaScript ?
Below case i have to display text Chief Administrative Officer.
main.js
angular.forEach($scope.rcsaErhTreeData, function(val) {
angular.forEach(val, function(val) {
console.log('this is the array value', val[0].text);
});
});
json.js
[{
"uid": null,
"index": 0,
"selected": null,
"expanded": null,
"id": 2701,
"text": "BAC Enterprise Wide",
"parentId": 0,
"items": [{
"uid": null,
"index": 0,
"selected": null,
"expanded": null,
"id": 4114,
"text": "Chief Administrative Officer",
"parentId": 2701,
"items": []
}]
}]

if you try the following code in your context you will get the result.
console.log(JSON.stringify(items[items.length - 1]));
The console will show you the stringified output...
Thanks,
Paras

I am not a Angular.js programmer, but the concept would be to:
1. Either do it in a loop and overwrite the variable value with the next value, that way, the last one will persist. -- Not recommended due to performance issues, and using a loop when it can be done without a loop.
Pseudo code:
var outVal='';
angular.forEach($scope.rcsaErhTreeData, function(val) {
angular.forEach(val, function(val) {
outVal = val[0].text);
});
});
console.log('this is the last item value', outVal);
Another approach would be find the length of the val array, and go to its last index to fetch its value. I am not a pro in this language so cannot give an example code. Sorry about that.