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Not being able to parse JSON doue to escape character

I have a jsonData like below, I am not able to parse it withjQuery.parseJSON() functon due to the presence of escape characters inside the value of the String and it gives me this error:
Error:
SyntaxError: "JSON.parse: bad escaped character at line X column Y of the JSON data"
jsonData which I am trying to parse using above function:
"reference_data": "{FastDelivery:'[\'facet.delivery.regions.1\'::[{ShippingCountry:\"US\"}]]'}"
One of way to enable parsing of this jsonData is by removing that escape character but I couldn't find any options/right way in Internet/StackOverflow to do it. Can somebody help me here with this small request?
Tried putting extra \ before each \ to make it \ before parsing - but it didnt work.

Adding variables in string JS

I am using a string to store some HTML. However, the string needs to have some variables. The method I am using to input this variables is encountering a problem. There are quotes in my HTML. Therefore the string is cutting short where I don't want it to.
base="<h2>"+data[i]+"</h2><br><button onclick='vote('"+data[i]+'"); return false'>Vote for ME!</button>"
However, I am getting this error.
'vote(' Uncaught SyntaxError: Unexpected end of input
Even if I remove the 2 single quotes in the brackets, I am getting an error.
'vote(Iron Man); return false': Uncaught SyntaxError: missing ) after argument list. NOTE: Iron Man is the value of data[i].
Thanks in advance!

You've got a ' and a " flipped around.
base="<h2>"+data[i]+"</h2><br><button onclick='vote('"+data[i]+'"); return false'>Vote for ME!</button>"
^^---- flip these two
Template literals can make complicated string concatenations much more readable and less error-prone as it would eliminate the need for most of the " double quotes in your code sample:
base = `<h2>${data[i]}</h2><br><button onclick="vote('${data[i]}'); return false">Vote for ME!</button>`

JSON.parse get "Uncaught SyntaxError: Unexpected token h"

I get the syntax error when I try to pass the following string:
JSON.parse("[{\"Date\": \"4/4/2016 4:15:19 PM\", \"Message\":\"<h3>New
Message</h3> Generated at 4/4/2016 4:15:19 PM.<br/><br/>Heavy Responsive
URL: <a href=\"https://performingarts.withgoogle.com/en_us\" ></a><br/><br/>
<img src=\"https://s-media-cache-ak0.pinimg.com/236x/06/bd/ac/06bdacc904c12abdce3381ba1404fd7e.jpg\" /> \"} ]");
I know that the error come from the link when I use double quote.
If I use single quote then no issue, but the data is getting from server side, I got no control over what going to pass in so I can only control on my side.
From what I read from the internet so far, I tried the following:
Use JSON.stringify first, then only use JSON.parse. I can parse
with no issue but problem occur when I try to loop the data. Instead
of looping it as JSON, the loop take the data as string and loop
every single text.
Escape every double quote which I'm currently doing, but it's not
working as shown above. But if I replace every double quote to
literal, I'm afraid some of the message that suppose to be double
quote will turn into literal as well, which will result in weird
looking message.
Please advice what other alternative I have to solve this.

You have JSON embedded in a JavaScript string literal.
" and \ are special characters in JSON and are also special characters in a JavaScript string literal.
href=\"https: escapes the " in the JavaScript string literal. It then becomes a " in the JSON. That causes an error.
When you want the " as data in the JSON you must:
Escape the " for JavaScript (as you are doing already)
Escape the " for JSON by adding a \.
Escape the \ for JavaScript
href=\\\"https:

JS - JSON.parse - preserve special characters

I'm running a NodeJS app that gets certain posts from an API.
When trying to JSON.parse with special characters in, the JSON.parse would fail.
Special characters can be just any other language, emojis etc.
Parsing works fine when posts don't have special characters.
I need to preserve all of the text, I can't just ignore those characters since I need to handle every possible language.
I'm getting the following error:
"Unexpected token �"
Example of a text i'm supposed to be able to handle:
"summary": "★リプライは殆ど見てません★ Tokyo-based E-J translator. ここは流れてくるニュースの自分用記録でRT＆メモと他人の言葉の引用、ブログのフィード。ここで意見を述べることはしません。「交流」もしません。関心領域は匦"�アイルランドと英国（他は専門外）※Togetterコメ欄と陰謀論が嫌いです。"
How can I properly parse such a text?
Thanks

You have misdiagnosed your problem, it has nothing to do with that character.
Your code contains an unescaped " immediately before the special character you think is causing the problem. The early " is prematurely terminating the string.
If you insert a backslash to escape the ", your string can be parsed as JSON just fine:
x = '{"summary": "★リプライは殆ど見てません★ Tokyo-based E-J translator. ここは流れてくるニュースの自分用記録でRT＆メモと他人の言葉の引用、ブログのフィード。ここで意見を述べることはしません。「交流」もしません。関心領域は匦\\"�アイルランドと英国（他は専門外）※Togetterコメ欄と陰謀論が嫌いです。"}';
console.log(JSON.parse(x));

You need to pass a string not as an object.
Example
JSON.parse('{"summary" : "a"}');
In your case it should be like this
JSON.parse(
'{"summary" : "★リプライは殆ど見てません★ Tokyo-based E-J translator. ここは流れてくるニュースの自分用記録でRT＆メモと他人の言葉の引用、ブログのフィード。ここで意見を述べることはしません。「交流」もしません。関心領域は匦�アイルランドと英国（他は専門外）※Togetterコメ欄と陰謀論が嫌いです。"}')

read a json string which has a "'" (malformed?)

I need to consume a service which is returning JSON. I have no influence whatsoever on that service (third party).
If I do
JSON.parse (data)
I get an
SyntaxError: Unexpected token
I know the service works because the error occurs depending on input parameters.
In other words, sometimes it definitely works! The HTTP response code is 200 so it is not some kind of access error, and it is repeatable.
Can I assume they are returning malformed JSON?
Writing the data as a text file to disk and reading it like this:
fs = require('fs')
fs.readFile 'output.json', '', (err, data) ->
if err?
console.log err
json = JSON.parse(data)
console.log json
returns
undefined:1
De L\'Embustier
^
SyntaxError: Unexpected token '
at Object.parse (native)
which is kind of strange because it seems as if the string is correctly escaped but it's nevertheless not being read correctly.
The file is 300+k; haven't seen how to attach it.
EDIT:
Response from jsonlint.com
Parse error on line 1297:
... "Address": "36 Rue De L\'Embust
-----------------------^
Expecting 'STRING', 'NUMBER', 'NULL', 'TRUE', 'FALSE', '{', '['
EDIT2:
Here is the whole file then:
http://pastebin.com/ACUfvPCx

The service is indeed returning malformed JSON.
There is no \' escape sequence in JSON. It's perfectly valid to escape any character in Javascript, but JSON uses a subset of the Javascript syntax and only allows escaping characters that actually could need escaping. As an apostrophe is not used as a string delimiter in JSON, it never needs escaping.
If you can't get the service fixed, you would need to request the JSON as plain text, replace the escaped apostrophes with just the apostrophe itself, then parse the text as JSON.