Parse json in objective-c for my iphone app - iphone

i have a problem parsing my json data for my iPhone app, I am new to objective-C. I need to parse the json and get the values to proceed. Please help. This is my JSON data:
[{"projId":"5","projName":"AdtvWorld","projImg":"AdtvWorld.png","newFeedCount":"0"},{"projId":"1","projName":"Colabus","projImg":"Colabus.png","newFeedCount":"0"},{"projId":"38","projName":"Colabus Android","projImg":"ColabusIcon.jpg","newFeedCount":"0"},{"projId":"25","projName":"Colabus Internal Development","projImg":"icon.png","newFeedCount":"0"},{"projId":"26","projName":"Email Reply Test","projImg":"","newFeedCount":"0"},{"projId":"7","projName":"PLUS","projImg":"7plusSW.png","newFeedCount":"0"},{"projId":"8","projName":"Stridus Gmail Project","projImg":"scr4.png","newFeedCount":"0"}]

On iOS 5 or later you can use NSJSONSerialization. If you have your JSON data in a string you can do:
NSError *e = nil;
NSData *data = [stringData dataUsingEncoding:NSUTF8StringEncoding];
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: data options: NSJSONReadingMutableContainers error: &e];
Edit To get a specific value:
NSDictionary *firstObject = [jsonArray objectAtIndex:0];
NSString *projectName = [firstObject objectForKey:#"projName"];

I would recommend using JSONKit library for parsing.
Here's a tutorial on how to use it.
You will basically end up with a dictionary and use objectForKey with your key to retrive the values.

JSONKit
or
NSJSONSerialization(iOS 5.0 or later)

I have had success using SBJson for reading and writing json.
Take a look at the documentation here and get an idea of how to use it.
Essentially, for parsing, you just give the string to the SBJsonParser and it returns a dictionary with an objectForKey function. For example, your code might look something like:
NSDictionary* parsed = [[[SBJsonParser alloc] init] objectWithString: json];
NSString* projId = [parsed objectForKey:#"projId"];

Use SBJson
SBJsonParser *parser = [[SBJsonParser alloc] init];
NSMutableDictionary *dicRes = [parser objectWithString:stringFromServer error:nil];

No need to use third party classes. Objective-c already includes handling JSON.
The class NSJSONSerialization expects an NSData object or reads from a URL. The following was tested with your JSON string:
NSString *json; // contains your example with escaped quotes
NSData *jsonData = [json dataUsingEncoding:NSUTF8StringEncoding];
NSError *error;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData:jsonData
options:NSJSONReadingAllowFragments error:&error]
For more options with NSJSONSerialization see the documentation.

Related

How to separate JSON response in iphone

I have an application in which I am having a json response like this.
{"success":"true","message":"You have logged in","pserial":"1"} and I am separating with ":".
And I am getting data like this pSerial:"1"} but I want only 1 value.
NSURL *url = [NSURL URLWithString:strUrl];
NSData *respData = [NSData dataWithContentsOfURL:url];
NSString *strResp = [[NSString alloc]initWithData:respData encoding:NSUTF8StringEncoding];
NSString *approvalString = [[strResp componentsSeparatedByString:#":"] objectAtIndex:3];
NSLog(#"pSerial:%#",approvalString);
for Example :
SBJsonParser *jsonPar = [[SBJsonParser alloc] init];
NSError *error = nil;
NSArray *jsonObj = [jsonPar objectWithString:jsonString error:&error];
id jsonObj = [jsonPar objectWithString:jsonString error:&error];
if ([jsonObj isKindOfClass:[NSDictionary class]])
// treat as a dictionary, or reassign to a dictionary ivar
else if ([jsonObj isKindOfClass:[NSArray class]])
// treat as an array or reassign to an array ivar.
Then get the value :
NSMutableArrary *userMutArr = [NSMutableArray array];
for (NSDictionary *dict in jsonObj)
{
User *userObj = [[[User alloc] init] autorelease];
[userObj setFirstName:[dict objectForKey:#"firstName"]];
[userObj setLastName:[dict objectForKey:#"lastName"]];
[userObj setAge:[[dict objectForKey:#"age"] intValue]];
[userObj setAddress:[dict objectForKey:#"address"]];
[userObj setPhoneNumbers:[dict objectForKey:#"phoneNumber"]];
[userMutArr addObject:userObj];
}
Hope you will understand. and read some Documents. it will help you.
It looks like you are in need of JSON Parsing. Here, what you want is JSON Parsing, not separating data from the JSON Response. JSON is the format of the data in which data is formatted in Key-Value pairs. You can fetch the "Value" of any object using the "Key".
Your first two lines are correct.
NSURL *url = [NSURL URLWithString:strUrl];
NSData *respData = [NSData dataWithContentsOfURL:url];
Now, you can parse JSON Response like this :
NSError* error;
NSDictionary* json = [NSJSONSerialization JSONObjectWithData:respData options:kNilOptions error:&error];
NSString *pSerial = [json objectForKey:#"pserial"];
This will give you the value of "pserial" from your response. Similarly, you can get the values for "success" and "message". You can check it using this line :
NSLog(#"pserial :: %#",pserial);
You need to parse the JSON Response String, you can use any JSON parser like:
https://github.com/stig/json-framework/
And in your code do:
NSString *strResp = [[NSString alloc]initWithData:respData encoding:NSUTF8StringEncoding];
NSDictionary *ResponseDictionary = [strResp JSONValue];
NSString * pSerial = (NSString*)[ResponseDictionary objectForKey:#"pserial"];
Dont separation by ":" just use JSONValue your response is like
// {"success":"true","message":"You have logged in","pserial":"1"}
// with SBJsonParser parse your object like this
NSDictionary *responseJson = [YOUR-OBJECT JSONValue];
Note: dont forget to add Json header file
Its better you use any OpenSource Json Parser
Here is a stack post Comparison of different Json Parser for iOS

How to generate a JSON string compatible with Objective-C syntax

I need some kind of json string generator for objective-c. Actually I thought there must be something like that but I could not find anything.To be specific, for example I have a json string like:
{"name":"abc","email":"def#ghi.com","password":"1"}
when I want to store it in objective c, I have to write it like:
#"{\"name\":""\"abc\""",\"email\":""\"def#ghi.com\""",\"password\":""\"1\"""}"
so it is confusing and hard to implement. Are there any generators or an easy way to implement it. Thanks
Convert your json string to dictionary...
NSData* data = [yourJsonString dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary* jsonDict = [NSJSONSerialization
JSONObjectWithData:data
options:kNilOptions
error:&error];
NSLog(#"jsonDict:%#",jsonDict);
You can use the native ios SDK API's for generating JSON data from NSDictionary / NSArray.
e.g.,
NSData *jsondata = [NSJSONSerialization dataWithJSONObject:(dictobject) options:NSJSONWritingPrettyPrinted error:&error];
NSString *str = [[NSString alloc] initWithData:jsondata encoding:NSUTF8StringEncoding];
may this helps!
Use it
Also Import"JSON.H"
NSDictionary *googleResponse = [[NSString stringWithContentsOfURL:[NSURL URLWithString:website] encoding: NSUTF8StringEncoding error: NULL] JSONValue];
be careful...in your original question, when referring to how to store it in objective-c, i think you made a mistake
you wrote :
#"{\"name\":""\"abc\"""
when it shoud be
#"{\"name\":\"abc\",....etc...
i think you doubled the quotes...be wary, cause in the beginning there already is one opening double-quote #", all the other needed quotes must be escaped like so \", and then also have an ending quote as well.
hope it helps

How to Parse this JSON in Objective-C

I'm new in iPhone programming.
I have to parse this data in JSON in Objective-C.
{"success":1,"check":[{"ChkKey":"2","ChkDeb":"Connection 1","ChkSSID":"Netgear-1111","ChkIP":"192.168.2.103","ChkBlk":"0"}]}
I follow the example for parsing data with Json. But this JSON is so different.
It is composed by two Array.
How can i proceed?
Thanks - A.b.
How about trying something like this ...
//JSON string
NSString *jsonString = #"{\"success\":1,\"check\":[{\"ChkKey\":\"2\",\"ChkDeb\":\"Connection 1\",\"ChkSSID\":\"Netgear-1111\",\"ChkIP\":\"192.168.2.103\",\"ChkBlk\":\"0\"}]}";
//Parse JSON string into an NSDictionary
NSError *e = [[NSError alloc] init];
NSDictionary *jsonData = [NSJSONSerialization JSONObjectWithData:[jsonString dataUsingEncoding:NSUTF8StringEncoding] options:NSJSONReadingMutableContainers error:&e];
//Output the value of success
NSLog(#"Success:%#", [jsonData objectForKey:#"success"]);
//Get data in the check array
NSDictionary *checkData = [[jsonData objectForKey:#"check"] objectAtIndex:0];
//Output the value of ChkSSID
NSLog(#"ChkSSID:%#", [checkData objectForKey:#"ChkSSID"]);

Converting an NSArray of Dictionaries to JSON array in iOS

I need to send an NSArray to the server in the JSON array format. How can I convert it to JSON. This is a sample of my NSArray that I have to pass.
array([0] => array('latitude'=>'10.010490',
'longitude'=>'76.360779',
'altitude'=>'30.833334',
'timestamp'=>'11:17:23',
'speed'=>'0.00',
'distance'=>'0.00');
[1] => array('latitude'=>'10.010688',
'longitude'=>'76.361378',
'altitude'=>'28.546305',
'timestamp'=>'11:19:26',
'speed'=>'1.614',
'distance'=>'198.525711')
)`
and the required format is like this
[
{ "latitude":"10.010490",
"longitude":"76.360779",
"altitude":"30.833334",
"timestamp":"11:17:23",
"speed":"0.00",
"distance":"0.00"
},
{
"latitude":"10.010688",
"longitude":"76.361378",
"altitude":"28.546305",
"timestamp":"11:19:26",
"speed":"1.614",
"distance":"198.525711"
}
]
Any one have solution? Thanks in advance.
NSDictionary *firstJsonDictionary = [NSDictionary dictionaryWithObjectsAndKeys:
#"10.010490", #"latitude",
#"76.360779", #"longitude",
#"30.833334", #"altitude",
#"11:17:23", #"timestamp",
#"0.00", #"speed",
#"0.00", #"distance",
nil];
NSDictionary *secondJsonDictionary = [NSDictionary dictionaryWithObjectsAndKeys:
#"10.010490", #"latitude",
#"76.360779", #"longitude",
#"30.833334", #"altitude",
#"11:17:23", #"timestamp",
#"0.00", #"speed",
#"0.00", #"distance",
nil];
NSMutableArray * arr = [[NSMutableArray alloc] init];
[arr addObject:firstJsonDictionary];
[arr addObject:secondJsonDictionary];
NSData *jsonData2 = [NSJSONSerialization dataWithJSONObject:arr options:NSJSONWritingPrettyPrinted error:&error];
NSString *jsonString = [[NSString alloc] initWithData:jsonData2 encoding:NSUTF8StringEncoding];
NSLog(#"jsonData as string:\n%#", jsonString);
The simplest and best approach !!!
To convert NSArray or NSMutableArray into jsonString you can first convert it into NSData and then further convert that into a NSString. Use this code
NSData* data = [ NSJSONSerialization dataWithJSONObject:yourArray options:NSJSONWritingPrettyPrinted error:nil ];
NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
It helped me and hope it helps you as well. All the best.
I would recommend the SBJson-Framework.
Converting an NSMutableArray is as simple as NSString *jsonString = [yourArray JSONRepresentation];
Edit: Jack Farnandish is right u have to transform it into a NSDictionary before you can convert it to Json. In my example the NSMutableArray has to contain the Dictionary. The Array is only needed to create the square brackets at the beginning and the end of the string.
You can use the build in JSON functions of iOS or use an external lib e.g. JSONKit to convert your data to JSON
First You must change you structure into NSDictionary class and NSArray containing NSDictionary objects, then try JSONKit in iOS 5 serialization works better than standard NSJSONSerialization.
#import <JSONKit/JSON.h>
NSArray *array = // Your array here.
NSString *json = [array JSONString];
NSLog(#"%#", json);
JSONKit performs significantly better than SBJson and others in my own and the author's benchmarks.
Check this tutorial, JSON in iOS 5.0 was clearly explained (serailization, deserailization).
Is the service you are calling a RESTful service?
If so, I'd strongly recommend using RestKit. It does object serialization/deserialization. It also handles all the networking underpinnings. Extremely valuable, and well maintained.

How to convert NSArray to NSData?

Can anyone tell me how to convert an NSArray to an NSData? I have an NSArray. I need to send it to an NSInputStream. In order to do that I need to convert the NSArray to an NSData.
Please help me, I'm stuck here.
Use NSKeyedArchiver (which is the last sentence of the post Garrett links):
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:array];
Note that all the objects in array must conform to the NSCoding protocol. If these are custom objects, then that means you need to read up on Encoding and Decoding Objects.
Note that this will create a fairly hard-to-read property list format, but can handle a very wide range of objects. If you have a very simple array (strings for instance), you may want to use NSPropertyListSerialization, which creates a bit simpler property list:
NSString *error;
NSData *data = [NSPropertyListSerialization dataFromPropertyList:array format:NSPropertyListBinaryFormat_v1_0 errorDescription:&error];
There's also an XML format constant you can pass if you'd rather it be readable on the wire.
On a somewhat related note, here's how you would convert the NSData back to an NSArray:
NSArray *array = [NSKeyedUnarchiver unarchiveObjectWithData:data]
I used this code.
NSError *error;
NSMutableData *jsonData = [[NSJSONSerialization dataWithJSONObject:yourDemoArray
options:0 // Pass 0 if you don't care about the readability of the generated string
error:&error] copy];
Swift :
let data = NSKeyedArchiver.archivedData(withRootObject: jsonArray)
print(data)
You can do this-
NSArray *array= [NSArray array];
NSData *dataArray = [NSKeyedArchiver archivedDataWithRootObject:array];
In iOS 9+ use this please:
NSArray *array = [[NSArray alloc] init];
NSData *data = [NSPropertyListSerialization dataWithPropertyList:array format:NSPropertyListBinaryFormat_v1_0 options:0 error:nil];
The older version of this was deprecated in iOS 8.
Swift 5
let data = try! NSKeyedArchiver.archivedData(withRootObject: array, requiringSecureCoding: true)