how to handle a json object with a sub object in the string. Here is an example
[{"_id":"1","Title":"Pineapple","Description":"Dole Pineapple","Icon":"icon.png","Actions":{"ACTION_PHOTO":"coupon.png", "ACTION_LINK":"google.com"}}]
How do you parse the second json "Actions" ?
What you have here is an array of dictionaries (with 1 entry), where one of the entries in the top level dictionary is also a dictionary. So you might have something like this to parse it:
NSError *e = nil;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error: &e];
if (jsonArray) {
NSDictionary *dictActions;
for (NSDictionary *dict in jsonArray) {
dictActions = [dict objectForKey:#"Actions"];
NSLog(#"The action link is: %#", [dictActions objectForKey#"ACTION_LINK"]);
}
} else {
NSLog(#"Error parsing JSON: %#", [e localizedDescription]);
}
Related
This question already has answers here:
How do I parse JSON with Objective-C?
(5 answers)
Closed 6 years ago.
I have the following json:
NSString *s = #"{"temperature": -260.65, "humidity": 54.05, "time": "2016-03-14T09:46:48Z", "egg": 1, "id": 6950, "no2": 0.0}";
I need to extract data from json to strings
NSString temperature
NSString humidity
NSString no2
How to do it properly?
you can use NSJSONSerialization class. first you need to convert your string to an NSData object after that you will get the JSON data. have a look on the code
// json s string for NSDictionary object
NSString *s = #"{\"temperature\": -260.65, \"humidity\": 54.05, \"time\": \"2016-03-14T09:46:48Z\", \"egg\": 1, \"id\": 6950, \"no2\": 0.0}";
// comment above and uncomment below line, json s string for NSArray object
// NSString *s = #"[{\"ID\":{\"Content\":268,\"type\":\"text\"},\"ContractTemplateID\":{\"Content\":65,\"type\":\"text\"}}]";
NSData *jsonData = [s dataUsingEncoding:NSUTF8StringEncoding];
NSError *error;
// Note that JSONObjectWithData will return either an NSDictionary or an NSArray, depending whether your JSON string represents an a dictionary or an array.
id jsonObject = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];
if (error) {
NSLog(#"Error parsing JSON: %#", error);
}
else
{
if ([jsonObject isKindOfClass:[NSArray class]])
{
NSLog(#"it is an array!");
NSArray *jsonArray = (NSArray *)jsonObject;
NSLog(#"jsonArray - %#",jsonArray);
}
else {
NSLog(#"it is a dictionary");
NSDictionary *jsonDictionary = (NSDictionary *)jsonObject;
NSLog(#"jsonDictionary - %#",jsonDictionary);
}
}
After making the NSURL Request in the completion block u can do this:-
NSMutableDictionary *s = [NSJSONSerialization JSONObjectWithData:data options:0 error:NULL];
NSString *temperature =[s objectForKey:#"temperature"];
NSString *humidity = [s objectForKey:#"humidity"];
I receive this JSON string from a web process
{
"result":"ok",
"description":"",
"err_data":"",
"data":[
{
"id":"14D19A9B-3D65-4FE2-9ACE-4C2D708DAAD8"
},
{
"id":"8BFD10B8-F5FD-4CEE-A307-FE4382A0A7FD"
}
]
}
and when I use the following to get the data:
NSError *jsonError = nil;
NSData *objectData = [ret dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary *json= [NSJSONSerialization JSONObjectWithData: objectData options:kNilOptions error: &jsonError];
NSLog(#"data: %#",[json objectForKey:#"data"]);
it gets logged as:
(
{
id = "14D19A9B-3D65-4FE2-9ACE-4C2D708DAAD8";
},
{
id = "8BFD10B8-F5FD-4CEE-A307-FE4382A0A7FD";
}
)
How can I parse the data as an NSDictionary with value and keys?
The web returns an object that has a property which is an array of objects, so...
NSDictionary *json= // your code
NSArray *array = json[#"data"];
for (NSDictionary *element in array) {
NSLog(#"%#", element);
// or, digging a little deeper
NSString *idString = element[#"id"];
NSLog(#"id=%#", idString);
}
I'm very new to Objective-C, I'm a hardcore Java and Python veteran.
I've created an Objective-C script that calls a URL and gets the JSON object returned by the URL:
// Prepare the link that is going to be used on the GET request
NSURL * url = [[NSURL alloc] initWithString:#"http://domfa.de/google_nice/-122x1561692/37x4451198/"];
// Prepare the request object
NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url
cachePolicy:NSURLRequestReturnCacheDataElseLoad
timeoutInterval:30];
// Prepare the variables for the JSON response
NSData *urlData;
NSURLResponse *response;
NSError *error;
// Make synchronous request
urlData = [NSURLConnection sendSynchronousRequest:urlRequest
returningResponse:&response
error:&error];
// Construct a Array around the Data from the response
NSArray* object = [NSJSONSerialization
JSONObjectWithData:urlData
options:0
error:&error];
//NSLog(object);
// Iterate through the object and print desired results
I've gotten this far:
NSString* myString = [#([object count]) stringValue];
NSLog(myString);
Which returns the size of this array, but how can I loop through this JSON object and print each element?
Here's the JSON I'm loading:
{
"country": "United States",
"sublocality_level_1": "",
"neighborhood": "University South",
"administrative_area_level_2": "Santa Clara County",
"administrative_area_level_1": "California",
"locality": "City of Palo Alto",
"administrative_area_level_3": "",
"sublocality_level_2": "",
"sublocality_level_3": "",
"sublocality":""
}
The top-level object your JSON object is a dictionary, not an array, as indicated by the curly braces. If you are not sure whether you are going to get an array or a dictionary back, you can do some safety checking like this:
// Construct a collection object around the Data from the response
id collection = [NSJSONSerialization JSONObjectWithData:urlData
options:0
error:&error];
if ( collection ) {
if ( [collection isKindOfClass:[NSDictionary class]] ) {
// do dictionary things
for ( NSString *key in [collection allKeys] ) {
NSLog(#"%#: %#", key, collection[key]);
}
}
else if ( [collection isKindOfClass:[NSArray class]] ) {
// do array things
for ( id object in collection ) {
NSLog(#"%#", object);
}
}
}
else {
NSLog(#"Error serializing JSON: %#", error);
}
Well for starters, the JSON you linked to is not an array, it is a dictionary.
NSDictionary* object = [NSJSONSerialization
JSONObjectWithData:urlData
options:0
error:&error];
There are a number of ways to iterate through all of the keys/values, and here is one:
for(NSString *key in [object allKeys])
{
NSString *value = object[key]; // assuming the value is indeed a string
}
My application returns a NSMutableData *receivedData.
I've opted for using NSJSONSerialization to parse this under the assumption that it would be easiest. I'm having extreme trouble trying to get my head around how to do it. I'm very new to Objective-C, from a Java background.
In Java I used gson to parse the JSON in to an array which I could use easily. I'm really struggling with this here.
My current code for parsing the JSON is:
NSError *e = nil;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: receivedData options: NSJSONReadingMutableContainers error: &e];
if (!jsonArray) {
NSLog(#"Error parsing JSON: %#", e);
} else {
for(NSDictionary *item in jsonArray) {
NSLog(#"Item: %#", item);
}
}
As provided by somebody on the internet. This works and prints two items to NSLog. result and header. Here is how the JSON looks:
{
"header":{
"session":"sessionid",
"serviceVersion":"1",
"prefetchEnabled":true
},
"result":"50ce82401e826"
}
However if there is an error the JSON can also look like this:
{
"header":{
"session":"sessionid",
"serviceVersion":"1",
"prefetchEnabled":true
},
"fault":{
"code":0,
"message":"someErrorCode"
}
}
How I want the code to work:
Check if there is a "fault" object
If there is, print fault.code and fault.message to NSLog
If there isn't, I know that my JSON contains result instead of fault
Print the value of result to NSLog
But I can't for the life of me figure out how to approach it. Can someone please give me some pointers?
your object appears to be a dictionary.
Try this out.
NSError *e = nil;
id jsonObj = [NSJSONSerialization JSONObjectWithData: receivedData options: NSJSONReadingMutableContainers error: &e];
NSArray *jsonArray = nil;
NSDictionary *jsonDict = nil;
if ([jsonObj isKindOfClass:[NSArray class]]){
jsonArray = (NSArray*)jsonObj;
}
else if ([jsonObj isKindOfClass:[NSDictionary class]]){
jsonDict = (NSDictionary*)jsonObj;
}
if (jsonArray != nil) {
// you have an array;
for(NSDictionary *item in jsonArray) {
NSLog(#"Item: %#", item);
}
}
else if (jsonDict != nil){
for (NSString *key in jsonDict.allKeys){
NSLog(#"Key: %# forItem: %#",key,[jsonDict valueForKey:key]);
}
}
else {
NSLog(#"Error: %#",e);
}
Trying to parse this JSON object in objective-C and creating an NSArray with these objects.
The first value is a counter and is specific for the object. All other values are unique.
{ "myData": [
["1","1","110","dollar","8.0","2.8","0.1","11.6"],
["2","1","110","euro","4.0","3.2","1.5","4.4"],
["3","1","120","rupier","6.0","2.9","1.3","10.8"],
["4","1","120","dinero","4.0","3.3","1.5","4.4"],
["5","2","130","drahmer","8.0","2.9","1.3","11.2"],
] }
Tried this code:
NSDictionary* json = [NSJSONSerialization
JSONObjectWithData:myData
options:kNilOptions
error:&error];
NSArray *currencyInformation = [json objectForKey:#"myData"];
But the objects are not there. Though the count of the array is 5.
Each object in the array is an array itself, so:
NSDictionary* json = [NSJSONSerialization
JSONObjectWithData:myData
options:kNilOptions
error:&error];
NSArray *currencyInformation = [json objectForKey:#"myData"];
for (NSArray *info in currencyInformation) {
// Then access each "column" with [info objectAtIndex:0,1,2,3,...]
}
In this data structure you would need to access things by index e.g
for (NSArray *currency in currencyInformation) {
NSLog(#"Currency: %#", [currency objectAtIndex:3]);
}
If you want to access things by key then you would need to change your JSON to use an array of objects instead of an array of arrays. Something like this:
{
"myData": [
{
"primaryKey" : 1,
"currency" : "dollar",
<other keys + values>...
},
]
}
In which case you could now do something like:
for (NSDictionary *currency in currencyInformation) {
NSLog(#"Currency: %#", [currency valueForKey:#"currency"]);
}