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Weird Error when trying to code a todo app

Just playing with JavaScript and I got an error an Uncaught SyntaxError: Unexpected token D in JSON at position 0
at JSON.parse ()
at app.js:22
The code in my JavaScript file error line is:
if (data) {
LIST = JSON.parse("TODO");
} else {
}

JSON.parse() will only work on strings or string variables that represent a JSON object, like
"
'item1': 50,
'item2': 80,
'item3': 100
"
in order to parse them into JSON objects
As you can tell, "TODO" cannot be parsed into a JSON object, but perhaps in your code there is a variable data which is a string representing JSON object. Most likely you will need to change that line to:
LIST = JSON.parse(data);

You are using json.parse on wrong data type.json.parse is made for objects while you are passing a string JSON.parse("TODO"). Note that "TODO" is a string and not an object.
Follow this example:
const todo = '{"name":"Empty the trash"}'
const obj = JSON.parse(todo);

Unable to parse JSON data properly in JQuery

This is my first time to convert JSON data with jQuery however, I get the following error when I try to convert the JSON string. Am I doing something wrong? I was searching for some simple sites about converting JSON string in jQuery, but most of the tutorial seems a bit difficult to understand. I would love to here some tips about converting jsons from url with jQuery if possible.
var obj = jQuery.parseJSON( '{"result":[{"id":"25","name":"loplo\n","score":"1198"},{"id":"58","name":"adjm","score":"1131"},{"id":"60","name":"dragon with ","score":"1083"},{"id":"57","name":"tDj","score":"799"},{"id":"59","name":"dragon with ","score":"452"},{"id":"55","name":"Donny","score":"450"},{"id":"56","name":"ajo ","score":"401"},{"id":"61","name":"make ","score":"392"}]}' );
Error message
Uncaught SyntaxError: Unexpected token
in JSON at position 35
at JSON.parse (<anonymous>)
at Function.m.parseJSON (jquery-1.11.1.min.js:4)
at leaderboard.js:16

The reason you're getting that error message is the \n in the first element that has the name: "loplo\n"
This is because new lines are allowed in JSON objects like that as they need to be either removed or escaped.
To get around this you can do
var obj = jQuery.parseJSON(mystring.replace(/\n/g,"\\n"));
You can read more about this here:https://bugs.chromium.org/p/v8/issues/detail?id=616

This is because you have the new line character as the value of loplo:
"loplo\n"
Remove the \n and it should work.
I don't recommend removing all of the \n with replace because you may want that. If you want to keep the \n, add a escape character before it, like this:
"loplo\\n" and it should work.

use this...
var e = '{"result":[{"id":"1351","identite":"RES ADDS","etat":"1","email":"udohou#gmail.com","telephone":"8787878","adresse":"COTONOU","nom_pays":"Togo","indicatif":"228"},{"id":"1350","identite":"MY DREAM","etat":"2","email":"dohouulrich#gmail.com","telephone":"5248525","adresse":"COTONOU","nom_pays":"Togo","indicatif":"228"},{"id":"1349","identite":"UN ","etat":"1","email":"dohouulrich#gmail.com","telephone":"66353364","adresse":"","nom_pays":"Benin","indicatif":"229"},{"id":"1348","identite":"DOHOU ULRICH SEMASSA & Fils","etat":"1","email":"dohouulrich#gmail.com","telephone":"66353364","adresse":"COTONOU","nom_pays":"Benin","indicatif":"229"},{"id":"1344","identite":"DC","etat":"2","email":"dohouulrich#gmail.com","telephone":"66353364","adresse":"","nom_pays":"Afghanistan","indicatif":"93"},{"id":"1343","identite":"AGAIN","etat":"2","email":"dohouulrich#gmail.com","telephone":"66353364","adresse":"","nom_pays":"Afghanistan","indicatif":"93"},{"id":"1342","identite":"SOCIAL LIMITED","etat":"3","email":"dohouulrich#gmail.com","telephone":"66353364","adresse":"","nom_pays":"Afghanistan","indicatif":"93"}]}';
var json = JSON.stringify(eval('(' + e + ')'));
var arr = $.parseJSON(json);
var resultData = arr['result'] ;
console.log(resultData) ;
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
I changed the Json String data because yours was not working. I think it is not well formated

Why does JSON.parse give invalid character

Edit: Solved... I needed to use JSON.stringify() here. Doh.
I am trying to JSON.parse() a response token and keep getting "SyntaxError: Invalid character" in Internet Explorer. (Not sure if this issue is present in Chrome due to CORS, but that's a different issue.)
console.log(response.token.isAdmin)
// false
console.log(JSON.parse(response.token.isAdmin))
// false
console.log(response.token.tokenValue)
// 36151b9e-ad0d-49de-a14b-5461489c7065
console.log(JSON.parse(response.token.tokenValue.toString()))
// SyntaxError: Invalid character
The same error occurs for any string I am trying to parse. If the source is not a string (boolean, integer) the parsing works fine.
Why isn't this working and how can I put my object into a string?

36151b9e-ad0d-49de-a14b-5461489c7065 is invalid JSON.
JSON.parse('36151b9e-ad0d-49de-a14b-5461489c7065'); // SyntaxError
Maybe you meant "36151b9e-ad0d-49de-a14b-5461489c7065", which is valid JSON.
JSON.parse('"36151b9e-ad0d-49de-a14b-5461489c7065"');
// 36151b9e-ad0d-49de-a14b-5461489c7065
Or maybe you wanted to stringify to JSON instead of parse
JSON.stringify('36151b9e-ad0d-49de-a14b-5461489c7065');
// "36151b9e-ad0d-49de-a14b-5461489c7065"

It appears that you are trying to parse a string that is not valid JSON.
You could parse a string like this:
var parseMe = '{ "tokenValue": "36151b9e-ad0d-49de-a14b-5461489c7065" }';
var parsed = JSON.parse(parseMe);
// parsed is now equal to Object {tokenValue: "36151b9e-ad0d-49de-a14b-5461489c7065"}
But you cannot parse something that is not formatted as JSON, like this:
var parseMe = '36151b9e-ad0d-49de-a14b-5461489c7065';
var parsed = JSON.parse(parseMe);
// Uncaught SyntaxError: Unexpected token b in JSON at position 5
If instead you wanted to get a JSON object parsed as a string, you could use JSON.stringify() like so:
var stringifyMe = { tokenValue: '36151b9e-ad0d-49de-a14b-5461489c7065' };
var stringified = JSON.stringify(stringifyMe);
// stringified is now equal to the string {"tokenValue":"36151b9e-ad0d-49de-a14b-5461489c7065"}

Javascript JSON parse and stringify for multi levels

I have a javascript object that contains a property with values of another json stringified object. I cannot get the printout version of the string back to object form. See the following code. the console.log output content of json string is exactly as right side of jsonFromStr. However, JSON.parse(json) is OK, while JSON.parse(jsonFromStr) is error. What is wrong here?
jsfiddle: http://jsfiddle.net/jma7889/qtmmpj2t/
level2Obj = { key2a: "foo", key2b: 3};
level2ObjJson = JSON.stringify(level2Obj);
level1Obj = {key1a: "bar", key1b: {level2ObjJson}};
json = JSON.stringify(level1Obj);
jsonFromStr = '{"key1a":"bar","key1b":{"level2ObjJson":"{\"key2a\":\"foo\",\"key2b\":3}"}}'; // same than json
objFromStrify = JSON.parse(json); // OK
objFromAssignedString = JSON.parse(jsonFromStr); // Uncaught SyntaxError: Unexpected token l in JSON at position 45

If you do this it will work:
jsonFromStr = '{"key1a":"bar","key1b":{"level2ObjJson":"{\\\"key2a\\\":\\\"foo\\\",\\\"key2b\\\":3}"}}';
The reason that your version does not work is that the escape sequence \" is resolved at that very moment, and so the actual value of jsonFromStr will be:
'{"key1a":"bar","key1b":{"level2ObjJson":"{"key2a":"foo","key2b":3}"}}'
... which is invalid JSON.
You need to keep those escapes unresolved in the JSON string, and this you do by escaping the escape sequence itself with additional slashes.

jsonFromStr = '{"key1a":"bar","key1b":{"level2ObjJson":{\"key2a\":\"foo\",\"key2b\":3}}}';
You have an extra "" for value of level2ObjJson key,replace jsonFromStr in your code with the above code .

How to properly decode a JSON string encoded using Html.Raw(Json.Encode(Model))?

I am encoding some model data into a html element like this:
#Html.Raw(Json.Encode(Model));
The json string returned looks like this:
{"TestList":[{"FrequencyType":"1X","GCDs":"585.6","Identifier":"6144","SeqNo":9306,"SeqNoSpecified":true,"TSeqNo":8314,"TSeqNoSpecified":true,"TestDescr":"HBsAg"},{"FrequencyType":"1X","GCDs":"585.6","Identifier":"6124","SeqNo":9295,"SeqNoSpecified":true,"TSeqNo":8315,"TSeqNoSpecified":true,"TestDescr":"HCV Ab"},{"FrequencyType":"1X","GCDs":"585.3","Identifier":"6","SeqNo":9729,"SeqNoSpecified":true,"TSeqNo":8309,"TSeqNoSpecified":true,"TestDescr":"HD Monthly LS"}],"Frequency":[{"Key":"ANNUAL","Value":"Annually"},{"Key":"BIMONTH","Value":"Bi-Monthly"},{"Key":"BIWEEK","Value":"Bi-Weekly"},{"Key":"MON","Value":"Monthly"},{"Key":"1X","Value":"One Time"},{"Key":"QTR","Value":"Quarterly"},{"Key":"SMAN","Value":"Semi-Annual"},{"Key":"WEEK","Value":"Weekly"}]};
When I try to parse this using JSON.parse, I get an error:
arrayTestList = [];
var jsonTestList = $('#TestList').text();
jsonTestList = JSON.stringify(jsonTestList);
arrayTestList = JSON.parse(jsonTestList);
alert(arrayTestList.TestList[0]); // <===== this line is failing
Unable to get value of the property '0': object is null or undefined
How do I convert this jsonTestList string into a javascript array so that I can access elements of arrayTestList properly?
Edit:
Sorry, I forgot to mention my edit. Basically above javascript code is inside a Partial View 2. The code where I am json encoding the model is in another Partial View 1. From P V 2, I cannot access the model object of P V 1, so I am just dumping the contents into a div tag, so that I can access this list TestList element.

Try removing this line:
jsonTestList = JSON.stringify(jsonTestList);
jsonTestList is already a JSON string

The issue is now resolved.
I was getting an invalid character, but couldn't immediately recognize which character it was that was causing the problem. I found that my JSON string isn't valid because of the trailing semicolon that was output by the Json.Encode method. I validated the JSON string # http://jsonlint.com.
Once I removed that semicolon, the json string is populated as a JavaScript array into arrayTestList object.
Now just this works, as mentioned in both the answers above, JSON.stringify is not needed.
var arrayTestList = [];
var jsonTestList = $('#TestList').text().replace(";","");
arrayTestList = JSON.parse(jsonTestList);
alert(arrayTestList.TestList[0]);

Why are you using Json.Encode? Also in your code, why are you writing redundant code first you are using JSON.stringify and the JSON.parse same object.
jsonTestList = JSON.stringify(jsonTestList);
arrayTestList = JSON.parse(jsonTestList);
As per my understanding just Html.Raw will work
In JavaScript
var jsonObject = #Html.Raw(Model.TestList); //Here you will get JavaScript Object
var jsonTestList = jsonObject.TestList;