Getting error signal sigabrt while converting type data to NsDictionary.

Question

Created Jan ’19

Replies 6

Boosts 0

Views 1.3k

Participants 3

Hello there, i have a json file in my computer. I am trying to read that by this code:

func ReadQuestion(){
        let path = "/Users/bishnudas/Documents/ExamFiles/questions.json"
        do {
            let data = try Data(contentsOf: URL(fileURLWithPath: path), options: .mappedIfSafe)
            if(data.count != 0){
                
                let jsonResult = try JSONSerialization.jsonObject(with: data)
                self.exampage.ExamQuestion = data
                self.exampage.showWindow(nil)
                self.window?.close()
            }
        } catch {
            print(error)
        }
    }

After reading that json file i am sending the data to another window and trying to convert that data like this:

func LoadQuestionPaper(){
        do{
            let QSJS = try JSONSerialization.jsonObject(with: ExamQuestion!, options:JSONSerialization.ReadingOptions.mutableContainers) as////! NSDictionary
//Getting error signal sigabrt here.        
    
        }catch {
            print(error)
        }
    }

Error message in console:

Could not cast value of type '__NSArrayM' (0x7fffa16f0fd0) to 'NSDictionary' (0x7fffa16f32d0).
2019-01-21 13:39:50.214466+0530 Unox Student Console[2071:66993] Could not cast value of type '__NSArrayM' (0x7fffa16f0fd0) to 'NSDictionary' (0x7fffa16f32d0).
Printing description of QSJS:
(NSDictionary) QSJS = <variable not available>

Can anyone help me to solve this, or can suggest me the right way to convert that data into dictionary please?

Boost

Answer 1

Claude31 OP

Jan ’19

What is the format of your JSON data (ExamQuestion) ? If it is a dictionary, I would try optional:

let QSJS = try JSONSerialization.jsonObject(with: ExamQuestion!, options:JSONSerialization.ReadingOptions.mutableContainers) as? NSDictionary

if let qsjs = QSJS  {   // note: var should start with lowercase

}

But isn't it an Array ?

Could you post ExamQuestion ? // Here also, should name it examQuestion

0

Answer 2

Bishnu Prasad OP

Jan ’19

Here is the format of ExamQuestion:

[
{
"id" : 1,
"type": "sub"
"text": "{RTF Text content}"
"num": 4,
"questions": [{
               "IsAns": null,
               .......
               .......
              }, 
               ....
              ]
}]

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Answer 3

Bishnu Prasad OP

Jan ’19

Actually i want to bind that data into an NSOutlineView, so that i want to convert that into a dictionary. Is there any other way to bind that data to an NSOutlineView in the UI of mac os application ? Can you suggest me please.

0

Answer 4

Claude31 OP

Jan ’19

What do you get if you print:

let QSJS = try JSONSerialization.jsonObject(with: ExamQuestion!, options:JSONSerialization.ReadingOptions.mutableContainers) as? NSDictionary

if let qsjs = QSJS  {   
      print(qsjs)
}

0

Answer 5

Bishnu Prasad OP

Jan ’19

Nothing is printing, the "qsjs" is showing nil.

0

Answer 6

OOPer OP

Jan ’19

The outermost symbol of your JSON is `[`, which indicates it is a JSON array, not JSON object.

You cannot convert JSON array into `NSDictionary`.

func loadQuestionPaper() {
    do {
        if let qsjs = try JSONSerialization.jsonObject(with: examQuestion!) as? [[String: Any]] {
            print(qsjs)
        } else {
            print("examQuestion cannot be deserialized as an Array")
        }
    } catch {
        print(error)
    }
}

Some other things...

- In almost all cases, `JSONSerialization.ReadingOptions.mutableContainers` has no meaning in Swift.

(Mutability is represented by `var`, not by an option.)

- Many Swift programmers follow one simple convention: Only type names start with capital letter. I recommend you to follow it.

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