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How can I extract data from a JSON file using javascript?

I have this simple variable which I am trying to extract data from. I've parsed it successfully to a json object and tried to print a value based on it a key. But all it says is "undefined". This example I provided is actually a snippet of the json I am trying to manipulate. The full file is actually a json object where one of the elements contains an array of many json objects (these are the ones I ultimately have to access). I have watched countless tutorials and have followed them exactly, but none seem to have this issue.
const x = `{
"status": "ok",
"userTier": "developer",
"total": 2314500,
"startIndex": 1,
"pageSize": 10,
"currentPage": 1,
"pages": 231450,
"orderBy": "newest"
}`;
JSON.parse(x);
console.log(x.status);
Can anybody suggest something I may be doing wrong? Thank you!

JSON.parse Return value
The Object, Array, string, number, boolean, or null value
corresponding to the given JSON text. - MDN
You have to assign the parsed result to some variable/constant from where you can use later that parsed value and then use that variable to extract data as:
const x = `{
"status": "ok",
"userTier": "developer",
"total": 2314500,
"startIndex": 1,
"pageSize": 10,
"currentPage": 1,
"pages": 231450,
"orderBy": "newest"
}`;
const parsedData = JSON.parse(x);
console.log(parsedData.status);
or you can directly get value one time after parsed as:
const x = `{
"status": "ok",
"userTier": "developer",
"total": 2314500,
"startIndex": 1,
"pageSize": 10,
"currentPage": 1,
"pages": 231450,
"orderBy": "newest"
}`;
console.log(JSON.parse(x).status);

Can valid JSON file consist of only one single object's description?

Example of given JSON file is as follows:
result = {
"name": "Foo",
"id": "10001",
"values": "1,2,3,4"
};

No, that is not valid JSON.
First, JSON is a string. What you have in the question is a JavaScript object literal expression assigned to the variable result.
Go to https://jsonlint.com/ , paste your file into the box, and click Validate. You will see the following output:
Error: Parse error on line 1:
result = { "name":
^
Expecting 'STRING', 'NUMBER', 'NULL', 'TRUE', 'FALSE', '{', '[', got 'undefined'
As you can see from the JSON specification , you can't have a variable as a top-level entity. The valid entities in a JSON string are:
a string
an object
an array
a number
Your result variable is not one of those things. It's a variable, which is only valid in JavaScript.

objLiteral = {
"name": "Foo",
"id": "10001",
"values": "1,2,3,4"
};
jsonString = '{ "name": "Foo", "id": "10001", "values": "1,2,3,4" }';
var myObj = JSON.parse( jsonString );
console.log(objLiteral);
console.log(myObj);
console.log(objLiteral.name);
console.log(myObj.name);
<pre>Sample javascript</pre>

Json to javascript dictionary

I have JSON data in the following structure, and I'm trying to parse it in order to work with the data using javascript.
JSON Data
{
"FirstItem": {
"id": 1,
"type": "foo",
"colours": ["blue", "black", "green"],
"reviews": {
"positive": ["The best", "unbelievable", "Awesome"],
"negative": ["Sh*t", "Awful", "Dire", "Terrible", "Appalling"],
"neutral": ["OK", "Meh"]
}
},
"SecondItem": {
"id": 2,
"type": "bar",
"colours": ["red", "white", "yellow"],
"reviews": {
"positive": ["Great", "Amazing", "Fantastic", "Perfect", "Uplifting"],
"negative": ["Terrible", "Shocking", "abysmal"],
"neutral": ["OK", "Standard", "Vanilla"]
}
}
}
I am trying to parse this using JSON.parse(), however this returns the following error:
JSON.parse: unexpected character at line 1 column 2 of the JSON data
I have previously worked with this same JSON structure using C#, and had to deserialise this into a dictionary - information can be found on this post
Question
How can I parse this JSON into a javascript object, which will allow me to loop and evaluate each item?

JSON is Javascript Object with double quoted key like what you have in sample. So you don't need to parse it again, see this for explanation. You can access data from it using its key or if in case you want to get reviews from SecondItem, you can access it with :
SecondItem.reviews
or
SecondItem['reviews']

Apparently you are trying to parse an already parsed object
x = {A:1}; // A javascript object
JSON.parse(x); // Error
this happens because JSON.parse will convert the object to a string first, getting "[object Object]" and then will try to parse this string.

json stringify failing when value is without double quotes

When I try to convert below json to string, getting unexpected desired output when the value is not surrounded with double quotes:
JSON data:
[
{
"Name": "param1",
"Type": "Integer",
"Default Value": 8778
},
{
"Name": "param2",
"Type": "Float",
"Default Value": 1.4
},
{
"Name": "param3",
"Type": "String",
"Default Value": true
},
{
"Name": "param4",
"Type": "String",
"Default Value": "test"
}
]
Current result:
[{"Name":"param1","Type":"Integer","Default Value":8778}, {"Name":"param2","Type":"Float","Default Value":**1.4**}, {"Name":"param3","Type":"String","Default Value":**true**}, {"Name":"param4","Type":"String","Default Value":**"test"**}]
Expected result:
[{"Name":"param1","Type":"Integer","Default Value":**"8778"**}, {"Name":"param2","Type":"Float","Default Value":**"1.4"**}, {"Name":"param3","Type":"String","Default Value":**"true"**}, {"Name":"param4","Type":"String","Default Value":**"test"**}]
I tried below code: but it is not working.
jsondata = JSON.stringify(confTableData);
jsondata = jsondata.replace(/:(\d+|\d*\.\d+)([,\}])/g, ':"$1"$2'); // only Integer & Float type values replaced
jsondata = jsondata.replace(/:(.)([,\}])/g, ':"$1"$2'); It gives strange result.
Can anyone help me on the regex pattern to match my requirement.

The JSON spec outlines what you're seeing as standard behavior and I'd recommend that you operate on the number as a number instead of a string.
If you need to modify this for some reason, you can use a "replacer" function as shown in the JSON.stringify spec.
var numbersAsStringsJSON = JSON.stringify(myData, replacer);
function replacer(key, value) {
if (typeof value === "number") { return String(value); }
else { return value; }
}
See JSFiddle for working example.

Numbers do not need to be wrapped in double quotes. Check out some of the examples on json.org.
If you want the numbers to be strings in JSON, you can make them strings before you stringify your object, e.g.:
var data = {
"Name": "param1",
"Type": "Integer",
"Default Value": 8778
};
data["Default Value"] = String(data["Default Value"]);
var json = JSON.stringify(data);
If you do it before you stringify the JSON you won't need to run a regex over it.

JSON validation

I'm trying to work with json-framework on iPhone to parse a json string.
When I'm calling this method:
NSDictionary *dictionary = [jsonString JSONValue];
I'm getting the error:
"Error Domain=org.brautaset.JSON.ErrorDomain Code=3 \"Object value expected for key:
Options\" UserInfo=0x4b5f390 {NSUnderlyingError=0x4b5f320 \"Expected value while
parsing array\", NSLocalizedDescription=Object value expected for key: Options}"
According to this json validator [1]: http://www.jsonlint.com// my json is not valid. But is that so??
My json string looks like this:
{
"Options": [
{
"ID": "7",
"A": "1",
"EAt": new Date(2011,
0,
7,
12,
30,
0),
"Type": "Binary",
}
}
* Edited Json: (still brings up an error)
{
"Options": [
{
"ID": "7",
"A": "1",
"EAt": new Date(2011,
0,
7,
12,
30,
0),
"Type": "Binary"
}
]
}

Your JSON is not valid.
It's because you can't create object instances within JSON. It's not a valid value.
new Date(2011, 0, 7, 12, 30, 0)
And you missed the closing array bracket. Everything else is ok.

remove the comma after ...Binary"
add a ] between the two } }.
Date cant be used like this, see How do I format a Microsoft JSON date? and http://msdn.microsoft.com/en-us/library/bb299886.aspx#intro_to_json_sidebarb
This is valid:
{
"Options": [
{
"ID": "7",
"A": "1",
"EAt": "new Date(2011,0,7,12,30,0)",
"Type": "Binary"
}
]
}

You can't instantiate Date objects (or any objects) in a JSON string.
You need to have whoever's responsible for the code that emits this JSON change it to emit valid JSON. They're putting out something now that can't work with any JSON parser. Maybe they have a customized JSON consumer that can handle such things, but this isn't standard JSON.
If I were you, I'd have them put the string of the current date into that field (so: "2011-07-01 12:30:00") and then parse that in your obj-cusing NSDateFormatter.
If whatever puts out that JSON isn't something you can change, you can always modify it locally before feeding it to the JSON library. It's just a string, nothing magical.