json interview questions
Top json frequently asked interview questions
I've looked on wikipedia and Googled it and read the official documentation, but I still haven't got to the point where I really understand what JSON is, and why I'd use it.
I have been building applications using PHP, MySQL and Javascript / HTML for a while, and if JSON can do something to make my life easier or my code better or my user interface better, then I'd like to know about it. Can someone give me a succinct explanation?
Source: (StackOverflow)
I am using the autocomplete feature of jQuery. When I try to retrieve the list of more then 17000 records (each won't have more than 10 char length), it's exceeding the length and throws the error:
Exception information:
Exception type: InvalidOperationException
Exception message: Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.
Can I set an unlimited length for maxJsonLength in web.config? If not, what is the maximum length I can set?
Source: (StackOverflow)
I need to serialize an object to JSON. I'm using jQuery. Is there a "standard" way to do this?
My specific situation: I have an array defined as shown below:
var countries = new Array();
countries[0] = 'ga';
countries[1] = 'cd';
...
and I need to turn this into a string to pass to $.ajax() like this:
$.ajax({
type: "POST",
url: "Concessions.aspx/GetConcessions",
data: "{'countries':['ga','cd']}",
...
Source: (StackOverflow)
How can I display JSON in an easy-to-read (for human readers) format? I'm looking primarily for indentation and whitespace, with perhaps even colors / font-styles / etc.
Source: (StackOverflow)
Using the newer ASP.NET Web API, in Chrome I am seeing XML - how can I change it to request JSON so I can view it in the browser? I do believe it is just part of the request headers, am I correct in that?
Source: (StackOverflow)
I've been messing around with JSON for some time, just pushing it out as text and it hasn't hurt anybody (that I know of), but I'd like to start doing things properly.
I have seen so many purported "standards" for the JSON content type:
application/json
application/x-javascript
text/javascript
text/x-javascript
text/x-json
But which is correct, or best? I gather that there are security and browser support issues varying between them.
I know there's a similar question, What MIME type if JSON is being returned by a REST API?, but I'd like a slightly more targeted answer.
Source: (StackOverflow)
Why does Google prepend while(1); to their (private) JSON responses?
For example, here's a response while turning a calendar on and off in Google Calendar:
while(1);[['u',[['smsSentFlag','false'],['hideInvitations','false'],
['remindOnRespondedEventsOnly','true'],
['hideInvitations_remindOnRespondedEventsOnly','false_true'],
['Calendar ID stripped for privacy','false'],['smsVerifiedFlag','true']]]]
I would assume this is to prevent people from doing an eval() on it, but all you'd really have to do is replace the while and then you'd be set. I would assume the eval prevention is to make sure people write safe JSON parsing code.
I've seen this used in a couple of other places, too, but a lot more so with Google (Mail, Calendar, Contacts, etc.) Strangely enough, Google Docs starts with &&&START&&& instead, and Google Contacts seems to start with while(1); &&&START&&&.
What's going on here?
Source: (StackOverflow)
I'd like to compare two arrays... ideally, efficiently. Nothing fancy, just true if they are identical, and false if not. Not surprisingly, the comparison operator doesn't seem to work.
var a1 = [1,2,3];
var a2 = [1,2,3];
console.log(a1==a2); // Returns false
console.log(JSON.stringify(a1)==JSON.stringify(a2)); // Returns true
JSON encoding each array does, but is there a faster or "better" way to simply compare arrays without having to iterate through each value?
Source: (StackOverflow)
Is there a (unix) shell script to format JSON in human-readable form?
Basically, I want it to transform the following:
{ "foo": "lorem", "bar": "ipsum" }
... into something like this:
{
"foo": "lorem",
"bar": "ipsum"
}
Source: (StackOverflow)
How should I parse JSON using Node.js? Is there some module which will validate and parse JSON securely?
Source: (StackOverflow)
I would like my JSON output in Ruby on Rails to be "pretty" or nicely formatted. Right now, I call the to_json method and my JSON is all on one line. At times this can be difficult to see if there is a problem in the JSON output stream.
Is there way to configure or a method to make my JSON "pretty" or nicely formatted in RoR?
Source: (StackOverflow)
After an AJAX request, sometimes my application may return an empty object, like:
var a = ({});
How can I check whether that's the case?
Source: (StackOverflow)
I have this JSON in a file:
{
"maps": [
{
"id": "blabla",
"iscategorical": "0"
},
{
"id": "blabla",
"iscategorical": "0"
}
],
"masks": [
"id": "valore"
],
"om_points": "value",
"parameters": [
"id": "valore"
]
}
I wrote this script which prints all of the json text:
json_data=open(file_directory).read()
data = json.loads(json_data)
pprint(data)
How can I parse the file and extract single values?
Source: (StackOverflow)
Is there a way to deserialize JSON content into a C# 4 dynamic type? It would be nice to skip creating a bunch of classes in order to use the DataContractJsonSerializer.
Source: (StackOverflow)