I'm appalled by the presence of highly-upvoted misinformation on such a highly-viewed question about a basic topic.
JSON strings cannot be quoted with single quotes. The various versions of the spec (the original by Douglas Crockford, the ECMA version, and the IETF version) all state that strings must be quoted with double quotes. This is not a theoretical issue, nor a matter of opinion as the accepted answer currently suggests; any JSON parser in the real world will error out if you try to have it parse a single-quoted string.
Crockford's and ECMA's version even display the definition of a string using a pretty picture, which should make the point unambiguously clear:
The pretty picture also lists all of the legitimate escape sequences within a JSON string:
\"\\\/\b\f\n\r\t\ufollowed by four-hex-digits
Note that, contrary to the nonsense in some other answers here, \' is never a valid escape sequence in a JSON string. It doesn't need to be, because JSON strings are always double-quoted.
Finally, you shouldn't normally have to think about escaping characters yourself when programatically generating JSON (though of course you will when manually editing, say, a JSON-based config file). Instead, form the data structure you want to encode using whatever native map, array, string, number, boolean, and null types your language has, and then encode it to JSON with a JSON-encoding function. Such a function is probably built into whatever language you're using, like JavaScript's JSON.stringify, PHP's json_encode, or Python's json.dumps. If you're using a language that doesn't have such functionality built in, you can probably find a JSON parsing and encoding library to use. If you simply use language or library functions to convert things to and from JSON, you'll never even need to know JSON's escaping rules. This is what the misguided question asker here ought to have done.
I'm appalled by the presence of highly-upvoted misinformation on such a highly-viewed question about a basic topic.
JSON strings cannot be quoted with single quotes. The various versions of the spec (the original by Douglas Crockford, the ECMA version, and the IETF version) all state that strings must be quoted with double quotes. This is not a theoretical issue, nor a matter of opinion as the accepted answer currently suggests; any JSON parser in the real world will error out if you try to have it parse a single-quoted string.
Crockford's and ECMA's version even display the definition of a string using a pretty picture, which should make the point unambiguously clear:
The pretty picture also lists all of the legitimate escape sequences within a JSON string:
\"\\\/\b\f\n\r\t\ufollowed by four-hex-digits
Note that, contrary to the nonsense in some other answers here, \' is never a valid escape sequence in a JSON string. It doesn't need to be, because JSON strings are always double-quoted.
Finally, you shouldn't normally have to think about escaping characters yourself when programatically generating JSON (though of course you will when manually editing, say, a JSON-based config file). Instead, form the data structure you want to encode using whatever native map, array, string, number, boolean, and null types your language has, and then encode it to JSON with a JSON-encoding function. Such a function is probably built into whatever language you're using, like JavaScript's JSON.stringify, PHP's json_encode, or Python's json.dumps. If you're using a language that doesn't have such functionality built in, you can probably find a JSON parsing and encoding library to use. If you simply use language or library functions to convert things to and from JSON, you'll never even need to know JSON's escaping rules. This is what the misguided question asker here ought to have done.
A JSON string must be double-quoted, according to the specs, so you don't need to escape '.
If you have to use special character in your JSON string, you can escape it using \ character.
See this list of special character used in JSON :
\b Backspace (ascii code 08)
\f Form feed (ascii code 0C)
\n New line
\r Carriage return
\t Tab
\" Double quote
\\ Backslash character
However, even if it is totally contrary to the spec, the author could use \'.
This is bad because :
- It IS contrary to the specs
- It is no-longer JSON valid string
But it works, as you want it or not.
For new readers, always use a double quotes for your json strings.
Can I use any special character in a key name in JSON? For example, is the following JSON valid?
{
"studentName": "John Doe",
"studentGrade": "9",
"marksIn%": "82"
}
First of all your declaration with array is incorrect.That is supposed to be an object but whatever case you need to check difference between object and array.However I assume that demo is an object with two key/properties which will be sent to server.
So declaration should look like this-
var demo = {};
demo.one = 'one';
demo.two = '<just>';
Then you should use to escape -
var treeBinding = encodeURIComponent(JSON.stringify(demo));
You can try something like this:
function arrayToObjectString(arr) {
var returnSrt = "{";
for (var key in arr) {
returnSrt += "\"" + key + "\" : \"" + arr[key] + "\"";
returnSrt += ","
}
returnSrt = returnSrt.substring(0, returnSrt.length - 1) + "}";
return returnSrt;
}
function main() {
var demo = [];
demo.one = 'one';
demo.two = '<just>'
console.log(JSON.stringify(demo))
var resultStr = arrayToObjectString(demo);
console.log(resultStr)
console.log(JSON.parse(resultStr));
}
main();I have tried using same json file document mentioned by you, the only change that i did is iterating the Json String. Please see the below code.
It works.
try{
List<Document> docList = [Select Id,Type,body, bodyLength, ContentType, Url from Document WHERE ID='01528000003FqHJAA0'];
String jsonStr='';
if(docList.size()>0)
{
Blob b = docList[0].body;
jsonStr = b.toString();
}
Map<String,Object> mapObj = (Map<String,Object>)JSON.deserializeUntyped(jsonStr);
for (String key : mapObj.keySet()){
System.debug('KEY :' + key);
System.debug('Value :' + mapObj.get(key));
}
}catch(Exception exe){
System.debug('EEROR OCCURED : '+exe.getMessage());
}
Have you tried escape sequence \u with hex value corresponding to special char ?
\u followed by four-hex-digits