Need a string JSON Validator

Question

I'm using newtonsoft's JSON.Net and loving every minute of it.

However, I am using JObject.Parse(jsonString) to grab a JToken from a response string. If I send invalid JSON, I get an exception. I can catch the exception, but I would like to, be able to test the string first before sending it to Parse.

Maybe something akin to JObject.TryParse() (which doesn't exist).

I'd even take bool ValidJson(string)

I know there's JSONLint out there, but I would really like to keep the external calls to a minimum.

Any ideas?

score 5 · Accepted Answer · edited Mar 17 '21 at 06:37

5

The simplest solution would be to write a function which calls JObject.Parse and returns false if it throws a Newtonsoft.Json.JsonReaderException.

edited Mar 17 '21 at 06:37

knocte

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answered Aug 01 '11 at 19:43

MRAB

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Return `true` for this invalid `JSON`: `{A:{"B": 1}}` – Mehdi Dehghani Dec 15 '16 at 09:53

score 3 · Answer 2 · edited Nov 14 '19 at 13:46

3

Use JContainer.Parse(str) method to check if the str is a valid Json. If this throws exception then it is not a valid Json.

JObject.Parse - Can be used to check if the string is a valid Json object
JArray.Parse - Can be used to check if the string is a valid Json Array
JContainer.Parse - Can be used to check for both Json object & Array

edited Nov 14 '19 at 13:46

Community

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answered Nov 26 '13 at 13:12

Senthilkumar Viswanathan

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score 0 · Answer 3 · edited May 23 '17 at 10:31

0

A working code snippet

public bool isValidJSON(string json)
{
    try
    {
        JToken token = JObject.Parse(json);
        return true;
    }
    catch(Exception ex)
    {
        return false;
    }
}

Thanks to MRAB

edited May 23 '17 at 10:31

Community

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answered Jun 19 '15 at 07:30

Durai Amuthan.H

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Return `true` for this invalid `JSON`: `{A:{"B": 1}}` – Mehdi Dehghani Dec 15 '16 at 09:52

Need a string JSON Validator

3 Answers3

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