asp.net - "<" character in JSON data is serialized to \u003c -

i have json object value of 1 element string. in string there characters "<rpc>". take entire json object , in asp.net server code, perform following take object named rpc_response , add data in post response:

var serializer = new system.web.script.serialization.javascriptserializer(); httpcontext.current.response.addheader("pragma", "no-cache"); httpcontext.current.response.addheader("cache-control", "private, no-cache"); httpcontext.current.response.addheader("content-disposition", "inline; filename=\"files.json\""); httpcontext.current.response.write(serializer.serialize(rpc_response)); httpcontext.current.response.contenttype = "application/json"; httpcontext.current.response.statuscode = 200; 

after object serialized, receive on other end (not web browser), , particular string looks like: \u003crpc\u003e.

what can prevent these (and other) characters not being encoded properly, still being able serialize json object?

the characters are being encoded "properly"!¹ use working json library correctly access json data - valid json encoding.

escaping these characters prevents html injection via json - , makes json xml-friendly. is, if json emited directly javascript (as done json valid² subset of javascript), cannot used terminate <script> element because relevant characters (e.g. <, >) encoded within json itself.

the standard javascriptserializer not have ability change behavior. such escaping might configurable (or different) in json.net implementation - but, shouldn't matter because valid json client/library must understand \u escapes.

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¹ rfc 4627: application/json media type javascript object notation (json),

any character may escaped. if character in basic multilingual plane (u+0000 through u+ffff), may represented six-character sequence: reverse solidus, followed lowercase letter u, followed 4 hexadecimal digits encode character's code point ..

see c# transform facebook response proper encoded string (which related json escaping).

² there a rare case when not hold, ignoring (or accounting for) that..