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iosjsonswiftswift3

Errors thrown from here are not handled

I've got this problem trying to parse a JSON on my iOS app:

Relevant code:

let jsonData:NSDictionary = try JSONSerialization.jsonObject(with: urlData! as Data, options: JSONSerialization.ReadingOptions.mutableContainers ) as! NSDictionary

/* XCode error ^^^ Errors thrown from here are not handled */

Could anybody help me ?

Solution

  • A possibly thrown error in let jsonData = try JSONSerialization ... is not handled.

    You can ignore a possible error, and crash as penalty if an error occurs:

    let jsonData = try! JSONSerialization ...

    or return an Optional, so jsonData is nil in error case:

    let jsonData = try? JSONSerialization ...

    or you can catch and handle the thrown error:

    do {
    let jsonData = try JSONSerialization ...
    //all fine with jsonData here
} catch {
    //handle error
    print(error)
}

    You might want to study The Swift Language