How to export .JSON file using NSMutableDictionary?

Question

I have NSMutableDictionary inside this values are present like this

{
    0 =     {
        imageangle = "0.09630692";
        imageheight = "129.0245";
        imagepath = "assets-library://asset/asset.PNG?id=BD849AC4-EDF2-4E05-B5F8-F5EE34385A97&ext=PNG";
        imagescalex = "85.48777";
        imagescaley = "85.48777";
        imagewidth = "129.0245";
        mainheight = 282;
        mainwidth = 316;
    };
    memes =     {
        alpha = 1;
        alphaFont = 1;
        blue = 1;
        blueFont = 0;
        green = 1;
        greenFont = "0.5";
        memestext = "Kishore kumar kumar ";
        red = 0;
        redFont = 1;
        textheight = 34;
        textscalex = 13;
        textscaley = "30.5";
        textwidth = 316;
    };
}

Using this i like to export this dictionary in .json file.

After that i am converting into JSONSTRING:

     NSError *error;
     NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dickeyjson                  options:NSJSONWritingPrettyPrinted                                                                                    error:&error];
NSString* aStr;
aStr = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];

My Question:

Is it possible to export it as .json and store it to local storage?

Why are you struggling, did you try using `NSJSONSerialization`? — luk2302, May 13 '16 at 14:38
Convert `Dictionary` to `json string` and then save that `string` into `file`. — Abhishek Sharma, May 13 '16 at 14:39
If you are going to store it locally, why bother with JSON? Just write the dictionary directly to a file. `NSDictionary` has built in methods for read and writing directly to/from a file. No JSON required. — rmaddy, May 13 '16 at 14:40
@luk2302 if i did NSJSONSerialization i am getting a json format ,how to export it as a file bro . — Kishore Kumar, May 13 '16 at 14:40
@AbhishekSharma but i am pressurised to store it a .json file — Kishore Kumar, May 13 '16 at 14:41
@luk2302 yes bro googled i am only confusing how to export it as a .json — Kishore Kumar, May 13 '16 at 14:43
please dont use word as bro on main site. this is not some social chat site. other thing is you are not showing exact issue which you are facing so that one can help you. just writing statements i am struggling is showing poor effort from your side — Shubhank, May 13 '16 at 14:43
if you want to export it , first you need to write it to a file with .JSON extension. Have you tried that ? — Teja Nandamuri, May 13 '16 at 14:45
As said before by @AbhishekSharma: First: Convert the `NSDictionary` to `JSON`. Secondly: a .json file is just a text file with ".json" as extension instead of ".text", so it's just a plain text file to save. There is plenty of question and answers about the two questions. You just have to combine them. Show what you have tried. — Larme, May 13 '16 at 15:00
@Shubhank y i am used bro means may be you guys are elder than me so to give respect i used its a common word — Kishore Kumar, May 13 '16 at 15:01
And you couldn't find something like that for the second part? http://stackoverflow.com/questions/1820204/objective-c-creating-a-text-file-with-a-string — Larme, May 13 '16 at 15:03
you have the string which is json, now just save it in documents directory or send it through mail. many options for you — Shubhank, May 13 '16 at 15:17

score 0 · Answer 1 · answered May 13 '16 at 17:19

You certainly can export a string to a .json file, and this would be an outline of a correctly error handling way to do so:

do {
    let jsonString = "{\"what\":\"ever\"}"
    let jsonFile = "file.json"
    guard let docs = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.AllDomainsMask, true).first else {
        throw NSError(domain: "what-no-Documents-folder??", code: 1, userInfo: nil)
    }
    let path = NSURL(fileURLWithPath: docs).URLByAppendingPathComponent(jsonFile)
    try text.writeToURL(path, atomically: false, encoding: NSUTF8StringEncoding)
} catch {
    fatalError("Writing failed!")
}

and to read it back in,

do {
    let path = NSURL(fileURLWithPath: "same as for writing")
    let jsonString = try NSString(contentsOfURL: path, encoding: NSUTF8StringEncoding)
}
catch {
    fatalError("Reading failed!")
}

However, it is probable that you want to put this JSON back into a dictionary when reading, yes? In that case, there's no need to convert to JSON, you should just use NSDictionary's writeToURL method directly, using the same outline as above; as I don't believe there's any JSON-representable object not conforming to NSCoder and therefore archivable with writeToFile/writeToURL.

score 0 · Answer 2 · answered May 13 '16 at 19:44

What exactly is the problem? You convert the dictionary to NSData using NSJSONSerialization. Then you write the NSData to a file using a variant of writeToFile: or writeToURL: There is no reason to go through NSString, it's just a waste of time, memory, and battery life.

To read the data, use dataWithContentsOfFile or dataWithContentsOfURL, and again NSJSONSerialization. If you use a mapped file, the NSData doesn't even use memory; that would be useful if your data is multiple megabytes.

How to export .JSON file using NSMutableDictionary?

2 Answers2