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How to pass variable to JSON without printing it as String

How to pass variable to JSON object and print it like JSON object?
I simply want to pass variable value in JSON and print it like JSON which can also be used in console.table(obj)
With Stringify:
var name = "someName";
const json = JSON.stringify('{"result":'+name+', "count":42}');
const obj = JSON.parse(json);
console.log(obj);
Without stringify
var name = "someName";
const json = '{"result":'+name+', "count":42}';
const obj = JSON.parse(json);
console.log(obj);
Using \"variableName\" it gets value in \"...\" and not the variable value
var name = "someName";
const json = '{"result":\"name\", "count":42}';
const obj = JSON.parse(json);
console.log(obj);
Solution:
var debugJSON = [];
var section_number = 1;
var i = 25;
var x = section_number-i;
tempJSON = {
"section" : section_number,
"index" : i,
"fieldname" : x,
"isValid" : "not required"
};
debugJSON.push(tempJSON);
console.log(debugJSON);
//console.table(debugJSON); //Problematic on Chrome Browser and Stack Overflow

JSON is a text representation of some data structure.
Unless you write a JSON encoder (and you don't), you don't have any reason to produce JSON manually. Attempting to generate JSON using string concatenation fails if the variable strings (name in this case) contain quotes or backslash. Escaping them could produce valid results but the code becomes bloated and difficult to read without any gain.
JavaScript provides the method JSON.stringify() to produce a JSON from any data and this is the best way to generate JSONs.
All you have to do is to build the data structure that you need to encode. In your example, the data structure is an object:
let name = "someName";
const original = {
result: name,
count: 42,
}
// encode
const json = JSON.stringify(original);
console.log(json);
// decode
data = JSON.parse(json);
console.log(data);
Running the code snippet here in page is not relevant because the output that it produces looks similar for both calls of console.log().
Run the code using Node.js or run it in the browser's console to see the values of json (it is a string) and data (it is an object).

A JSON is quite literally a JavaScript object, so you don't treat it as a string, you work with objects, which you can later stringify if need be.
In your case, you don't want to pass a variable in a string, you should pass it in an object like so:
// Declaration of name
let name = 'someName';
// Create object and store name
const json = {
result: name,
count: 42
};
// Log object as JSON and as string
console.log(json);
console.log(JSON.stringify(json));
The first log returns your object as exactly that, an object, the second log, converts it into a string to do so as you please with it!

JSON.stringify not printing all fields [duplicate]

I must be missing something here, but the following code (Fiddle) returns an empty string:
var test = new Array();
test['a'] = 'test';
test['b'] = 'test b';
var json = JSON.stringify(test);
alert(json);
What is the correct way of JSON'ing this array?

JavaScript arrays are designed to hold data with numeric indexes. You can add named properties to them because an array is a type of object (and this can be useful when you want to store metadata about an array which holds normal, ordered, numerically indexed data), but that isn't what they are designed for.
The JSON array data type cannot have named keys on an array.
When you pass a JavaScript array to JSON.stringify the named properties will be ignored.
If you want named properties, use an Object, not an Array.
const test = {}; // Object
test.a = 'test';
test.b = []; // Array
test.b.push('item');
test.b.push('item2');
test.b.push('item3');
test.b.item4 = "A value"; // Ignored by JSON.stringify
const json = JSON.stringify(test);
console.log(json);

Nice explanation and example above. I found this (JSON.stringify() array bizarreness with Prototype.js) to complete the answer. Some sites implements its own toJSON with JSONFilters, so delete it.
if(window.Prototype) {
delete Object.prototype.toJSON;
delete Array.prototype.toJSON;
delete Hash.prototype.toJSON;
delete String.prototype.toJSON;
}
it works fine and the output of the test:
console.log(json);
Result:
"{"a":"test","b":["item","item2","item3"]}"

I posted a fix for this here
You can use this function to modify JSON.stringify to encode arrays, just post it near the beginning of your script (check the link above for more detail):
// Upgrade for JSON.stringify, updated to allow arrays
(function(){
// Convert array to object
var convArrToObj = function(array){
var thisEleObj = new Object();
if(typeof array == "object"){
for(var i in array){
var thisEle = convArrToObj(array[i]);
thisEleObj[i] = thisEle;
}
}else {
thisEleObj = array;
}
return thisEleObj;
};
var oldJSONStringify = JSON.stringify;
JSON.stringify = function(input){
if(oldJSONStringify(input) == '[]')
return oldJSONStringify(convArrToObj(input));
else
return oldJSONStringify(input);
};
})();

Another approach is the JSON.stringify() replacer function param. You can pass a 2nd arg to JSON.stringify() that has special handling for empty arrays as shown below.
const arr = new Array();
arr.answer = 42;
// {"hello":"world","arr":{"answer":42}}
JSON.stringify({ hello: 'world', arr }, function replacer(key, value) {
if (Array.isArray(value) && value.length === 0) {
return { ...value }; // Converts empty array with string properties into a POJO
}
return value;
});

Alternatively you can use like this
var test = new Array();
test[0]={};
test[0]['a'] = 'test';
test[1]={};
test[1]['b'] = 'test b';
var json = JSON.stringify(test);
alert(json);
Like this you JSON-ing a array.

Json has to have key-value pairs. Tho you can still have an array as the value part. Thus add a "key" of your chousing:
var json = JSON.stringify({whatver: test});

How I can filter a value corresponding to a specific key in a string?

In my JS code, i have string as
s = "{\"selector\":{\"owner\":\"tom\"}}"; // originally this is a query response
I want to extract the value of 'owner' which is tom in another variable, s1.
What would be the easiest way to do it?

To convert your data to an object use obj = JSON.parse(s)
Then obj.selector.owner Or
obj["selector"]["owner"] which is the recommended way to get JavaScript object values...

You are not selecting the right properties when accessing your response data. Also you do not need to use toString in JSON.parse. Because your response is already a string data.
You want to convert string data by using JSON.parse
Demo:
//Response # 1
let findOwner = "{\"selector\":{\"owner\":\"tom\"}}"
//Parse Data
let parseData = JSON.parse(findOwner)
console.log(parseData.selector.owner) //Tom
//Response # 2
let findOwner2 = "{\"response\":{\"colour\":\"black\",\"make\":\"Tesla\",\"model\":\"S\",\"owner\":\"Adriana\"}}"
//Parse Data
let parseData2 = JSON.parse(findOwner2)
console.log(parseData2.response.owner) //Adriana

You can use a function for this:
function get(path, obj) {
return path.split('.').reduce((acc, current) => acc && acc[current], obj)
}
const obj = "{\"selector\":{\"owner\":\"tom\"}}"
const parsed = JSON.parse(obj)
get('selector.owner', parsed) // return 'tom'

How can I turn a json object into a javascript array

So, I need to convert a json object like this {"0":"sometext","1":"someothertext"} into a javascript array with the index matching the integer and the data at the index the string. I tried using JSON.parse() but it didn't work since this happens.
var json = '{"0":"sometext","1":"someothertext"}';
var obj = JSON.parse(json);
//Then when I would want to assign a part of the object to a variable this gives me an error
var somevar = obj.0;

You can simply iterate over every property in the object and assign them as values in the array:
var obj = {"0":"sometext","1":"someothertext"};
var arr = [];
Object.keys(obj).forEach(function (key) {
arr[key] = obj[key]
});

Use bracket notation:
Change
var somevar = obj.0;
to
var somevar = obj[0];

Why I can't parse JSON in JavaScript?

JSON contains one object:
results[0] = { 'MAX(id)': 1 }
And this code doesn't work:
var text = results[0];
var obj = JSON.parse(text);
console.log(obj.MAX(id));

results[0] is already an object type
You can parse only from string to object like this:
JSON.parse('{ "MAX(id)": 1 }');

Your object is already a JSON. You don't need to parse it.
To access MAX(id) property, you can use [] notation as follows:
results[0] = { 'MAX(id)': 1 };
console.log(results[0]['MAX(id)']);

Your result[0] is a real javascript object. JSON.parse transforms text into objects, so you can't parse other objects with it.

var results = { 'MAX(id)': 1 };
//var text = results;
//var obj = JSON.parse(text);
alert(results['MAX(id)']);