How to pass multiple double quotes in JSON? - javascript

I should construct and pass following text in my JSON scheme. Here is how it should look:
r"""any-text-goes-here"""
Here is how I decided to construct it:
function make(text) {
return `r"""${text}"""`;
}
The function above takes any string and converts it to desired format. But, when I return it in my API as one of fields of JSON, it looks like following:
"r\"\"\"any-text-goes-here\"\"\""
I want to avoid backslashes. I understand that those slashes is needed by Javascript to properly work, but can I remove them, because client side awaits how I described above. Is it possible technically? How can I solve problem?

JSON strings are delimited by " characters.
" characters can be included in a JSON string only by using an escape sequence.
Escape sequences start with a \.
You can't avoid the backslashes.
See the grammar from the JSON website:

Related

losing escape characters passing a path in json from Xamarin Forms c# to javascript

I have a Xamarin Forms app that is calling javascript and sending as a parameter a JSON string that contains a path. When it leaves c# the back slashes have been double-escaped like this:
"myreturnfunc('', '{\"statusCode\":\"200\",\"path\":\"\\\\temp\\\\Uploads\\\\100650\\\\IMG_20200107_094705_5.jpg\"}');"
but when it gets into myreturnfunc only single back slashes remain:
"{"statusCode":"200","path":"\temp\Uploads\100650\IMG_20200107_094705_5.jpg"}"
which fails on JSON.parse. What do I need to do to allow the escaped \'s to come through? I call this method from another javascript function as well, and when called from there it comes through in the correct format:
"{"path":"\\temp\\Uploads\\100650\\IMG_20200107_094705_5.jpg","statusCode":"200"}"
Json.parse typically encounters two escapes when the json.parse parameter contains the transition characters, the first being the escape of the string itself and the second being the escape of the actual js object.
for example,your string \"path\":\"\\\\temp\\\\Uploads\\\\100650\\\\IMG_20200107_094705_5.jpg\" above
First parser extracted strings think first \ escape the second \ and the third \ escape the fourth \, that is to say, the actual output string is "path":"\\temp\\Uploads\\100650\\IMG_20200107_094705_5.jpg" (could be verified by console.log)
Then there is another escape when it is formally converted to a js object,the finally result will be "path":"\temp\Uploads\100650\IMG_20200107_094705_5.jpg"
So if you want one \ in a js object, you need four \ in a json string

Escape dotnet resources in javascript

I need to read dot ner reesources string in java script as mention below.
var resources = #Html.ResourceStrings("Home_General_", Resources.ResourceManager);
The above line will render all the resources (from Dot net resource file) which start with resource key as "Home_General_"
Some of the values from the resources are like "Hi "XYZ" are you there" i.e The string contains quotes character.
If the string has quotes the above call fails.
The one way to avoid this problem is escape the special character as "Hi \"XYZ\" are you there"
Any other way where we can avoid this, As I don't want to pollute my resource string with lot of escape (\) characters.
You need to Javascript-escape any string when you render it as a Javascript string literal.
You must also remove the outer quotes from the string resource; that should be text, not a half-valid Javascript expression.
Use code like this to retrieve a single resource string:
var resourceXYZ = '#Html.Raw(HttpUtility.JavaScriptStringEncode(Resources.ResourceManager.GetString("Home_General_XYZ")))';
We do the following:
We get the resource string via Resources.ResourceManager.GetString().
We pass the result to HttpUtility.JavaScriptStringEncode to escape any special characters in JavaScript.
We pass the result to Html.Raw() to prevent Razor from applying HTML encoding on this string.
We then output the text enclosed in single quote quaracters into the page.
The function Html.ResourceStrings is not a standard function that is part of MVC. Someone at your place must have written it. If you show us this code, we could tell you how to rewrite it to return valid JavaScript literals.
You could wrap your #Html.ResourcesString(...) with HttpUtility.JavaScriptStringEncode which will handle all escape issues.
var resources = #HttpUtility.JavaScriptStringEncode(Html.ResourceStrings("Home_General_", Resources.ResourceManager));

Why can't Javascript parse this JSON array from a string literal?

What I am trying to do is simple. Parse this array holding json objects into a Javascript array.
var merchantsJson = JSON.parse('[{"id":61693,"name":"Más"},{"id":61690,"name":"\u0027\u0022\u003C/div\u003E"}]');
But the unicode character \u003C seems to be breaking the parser. In the chrome console I see "Uncaught SyntaxError: Unexpected token <"
A little more info. The above is what the code is evaluated to. In reality the code contains a jsp expression.
var merchantsJson = JSON.parse('${jsonArr}');
If I remove the single quotes, there is no issue, but eclipse give me an "missing semicolon" error message. Is it possible to parse the array with the quotes as I am trying to do?
The interpolation of ${jsonArr} is already a JavaScript object. When you wrap it in '${jsonArr}' this turns it into a string and you have to use JSON.parse.
There's no need to make it a string. You can just do var merchantsArray = ${jsonArr}. JSON constructs are already interoperable with JavaScript code.
Because there's an extra " in your string literal that is encoded by \u0022:
> '[{"id":61693,"name":"Más"},{"id":61690,"name":"\u0027\u0022\u003C/div\u003E"}]'
[{"id":61693,"name":"Más"},{"id":61690,"name":"'"</div>"}]
In short, your JSON in the string is invalid. You would need to escape the unicode escape sequences for the quotes in the string literal ("'\u0022</div>"), by using
JSON.parse('[{"id":61693,"name":"Más"},{"id":61690,"name":"\u0027\\u0022\u003C/div\u003E"}]'
// ^
or escape the quote character ("'\"</div>"):
JSON.parse('[{"id":61693,"name":"Más"},{"id":61690,"name":"\u0027\\\u0022\u003C/div\u003E"}]');
// ^^
However, there actually is no need to use JSON at all. Just output a JS array literal into your code:
var merchantsJson = ${jsonArr};
Try to replace \u with \\u. If you don't, JSON parser receives already decoded Unicode, which created polluted JSON.
It's not because of \u003C, rather the \u0022 character is causing the issue, since it's a quotation mark and JavaScript treats it literally ending the string.
You need to escape that character: \\u0022 .
you have to use special character in your JSON string, you can escape it using \ character.
you need to replace \ with \\.
[{\"id\":61693,\"name\":\"Más\"},{\"id\":61690,\"name\":\"\\u0027\\u0022\\u003C/div\\u003E\"}]

How to deserialize Json object which contain control character using Dojo.fromJson

I am using Dojo.fromJson to convert json string to javascript object, but throw exception. Because, there are control characters such as ',\n,\r in the json string.
How can I solve this problem in dojo? convert json string to javascript object, even if there are control characters.
I use Newtonsoft.JsonConvert.SerializeObject to convert C# oject to json data. Json Object: {"name":"'\"abc\n123\r"} then, I use Dojo.fromJson(' {"name":"'\"abc\n123\r"}') to convert json data to javascript object.
Thank you very much!
Problem, i believe is the double-quote which should be escaped by triple backslashes. You can use "native browser JSON decode" as searchterm for "dojo fromJson" synonym.
Without knowing my way around C# - I havent tested but i believe following should work:
string c_sharp_name = "'\"abc\n123\r";
// C#Object.name
c_sharp_name = c_sharp_name.
replace('"', '\\"'). // maybe add a slash on serverside
replace('\n', '\\\n').
replace('\r', '\\\r');
since
while this fails:
{"name":"'\"abc\n123\r"} // your single backslash
this would work:
{"name":"'\\\"abc\\\n123\\\r"} // working triple backslash escape

How to add "\" character in JSON?

I want to add JSON data with the following string value:
json = "d:\xyz\abc";
This value is coming from a database at runtime. When I am going to display it in datatable, JSON formatting error is displayed. My requirement is that the above value will be displayed as it is in the datatable. Please help.
Escape it with another \:
var json = "d:\\xyz\\abc";
You'd better use a JSON library for your programming language. You don't retrieve database values directly with jquery, aren't you?
So, you'd use something like JSON.escape(my_string_from_db), or, in Ruby language I usually do my_string.to_json.
This will automatically escape everything that needs to be escaped.
Change to this:
json = "d:\\xyz\\abc";
See this question for further information
\ is the escape character in JavaScript strings, it gives special meaning to the character following the slash. Like \t is a tab character, \n is a new line. To put a backslash literal you'll need to use \\
The first backslash says the next character is going to be special, the following backslash says "oh, it's just a backslash."

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