iOS Swift:"JSON text did not start with array or object and option to allow fragments not set."

Question

When I converting Json string to dictionary in swift I got the Issue:Error Domain=NSCocoaErrorDomain Code=3840 "JSON text did not start with array or object and option to allow fragments not set." UserInfo={NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.}

I don't know to fix the issue please give idea for fix the issue.Here I gave my code what i am tried..

The method for converting Json string to dictionary is,

func convertToDictionary(from text: String) throws -> [String: String] {
    guard let data = text.data(using: .utf8) else { return [:] }
    let anyResult: Any = try JSONSerialization.jsonObject(with: data, options: [])
    return anyResult as? [String: String] ?? [:]
}

The Json String is: "[{\"propertyId\":\"1\",\"inspectionTemplateId\":1118,\"value\":[{\"widgetControllerId\":141,\"value\":\"Flood Summary Name\"},{\"widgetControllerId\":142,\"value\":\"Did the property flood?\"},{\"widgetControllerId\":143,\"value\":\"no\"}]}]"

And the Usage of method was:

let jsonString = NSString(data: responseObject as! Data, encoding: String.Encoding.utf8.rawValue)!
        print(jsonString)
        do {
            let dictionary:NSDictionary = try self.convertToDictionary(from: jsonString as String) as NSDictionary
            print(dictionary)
        } catch {
            print(error)
        }

Your JSON is invalid. Try running your test through a JSON validator first. — john elemans, Jan 29 '18 at 07:08
try using `try JSONSerialization.jsonObject(with: data, options: [.allowFragments])` — Reinier Melian, Jan 29 '18 at 07:11
Your JSON is an Array at top level by the way, an array of dictionary, but once you removed "\" before the `"`, it seems valid so you shouldn't get that error, you should get another one: returning empty: `[:]`. — Larme, Jan 29 '18 at 07:12
Why do you convert `Data` to `(NS)String` and then back to `Data`? Print the data (`print(data as NSData)`) and post the first bytes. And don't use `NSString` and `NSDictionary` in Swift. — vadian, Jan 29 '18 at 08:03
Possible duplicate of [JSON text did not start with array or object and option to allow fragments not set](https://stackoverflow.com/questions/21452385/json-text-did-not-start-with-array-or-object-and-option-to-allow-fragments-not-s) — AshvinGudaliya, Apr 05 '18 at 12:38
Possible duplicate of [JSON Error when posting JSON](https://stackoverflow.com/questions/39059948/json-error-when-posting-json) — Naresh, Sep 24 '18 at 10:27
See my answer , https://stackoverflow.com/questions/33951401/json-text-did-not-start-with-array-or-object-and-option-to-allow-fragments-not-s/33951557 — Naresh, Jan 07 '19 at 06:27

score 23 · Answer 1 · edited Jun 20 '18 at 00:54

23

Read the error gentleman. Error is 'allow fragments not set'. Just Just just set .allowFragments. That's it. (Make sure response is not malformatted)

JSONSerialization.jsonObject(with: data!, options: .allowFragments)

edited Jun 20 '18 at 00:54

Pang

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answered Jun 19 '18 at 17:24

Aaban Tariq Murtaza

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14

Useful :) However, are there any global solution to check the data in JSON? Because now I have: Error serializing json Error Domain=NSCocoaErrorDomain Code=3840 "Invalid value around character 0." – J A S K I E R Jul 08 '18 at 19:28
@Oleksandr I assume its bc the plist is wrapped inside xml – John Smith Apr 03 '20 at 13:43
Sorry, but where exactly is this setting found? – RonH Jun 05 '21 at 17:53

score 3 · Answer 2 · edited Jun 20 '18 at 00:55

3

You can try this:

let str = "[{\"propertyId\":\"1\",\"inspectionTemplateId\":1118,\"value\":[{\"widgetControllerId\":141,\"value\":\"Flood Summary Name\"},{\"widgetControllerId\":142,\"value\":\"Did the property flood?\"},{\"widgetControllerId\":143,\"value\":\"no\"}]}]".utf8
let json = try! JSONSerialization.jsonObject(with: Data(str), options: [])
print(json)

edited Jun 20 '18 at 00:55

Pang

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answered Jan 29 '18 at 07:09

Kamani Jasmin

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jcpennypincher · Answer 3 · 2021-08-13T18:38:45.990

0

This type of issue can also occur if you have a misconfigured server or your server is unreachable. If you receive this type of error from JSON deserialization you may try converting the data to a string and print it out. It may reveal an error like "502 Bad Gateway"

edited Aug 13 '21 at 18:38

answered Sep 01 '20 at 00:18

jcpennypincher

3,970
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iOS Swift:"JSON text did not start with array or object and option to allow fragments not set."

3 Answers3

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