How to use setHTTPBody method with NSString as argument? - ios

I have to use a webservice which takes HTTP Body format as the following
{
"ScreenID" : "screenID1",
"DeviceID" : "E7EF8DCE-CE8A-4F0C-BBC5-F080C29FEF29",
"SessionStartTime" : "2014-03-27T06:50:15",
"SessionEndTime" : "2014-03-27T06:50:15"
}
Now when i use NSMutableURLRequest instance
it takes NSData instance as an argument
The code is as follows :-
NSMutableURLRequest *request = [[NSMutableRequest alloc] initWithURL:#"someurl"]
[request setHTTPMethod:#"POST"];
[request setValue:#"application/json" forHTTPHeaderField:#"Content-Type"];
[request setValue:cipher forHTTPHeaderField:#"Cipher"];
NSData *jsonData;
if ([NSJSONSerialization isValidJSONObject:dict]) {
NSError *error;
jsonData = [NSJSONSerialization dataWithJSONObject:dict options:NSJSONWritingPrettyPrinted error:&error];
if (!jsonData) {
NSLog(#"json Data %#",error.description);
} else {
NSString *JSONString = [[NSString alloc] initWithBytes:[jsonData bytes] length:[jsonData length] encoding:NSUTF8StringEncoding];
NSLog(#"JSON String %#",JSONString);//[JSONString dataUsingEncoding:NSUTF8StringEncoding]
[request setHTTPBody:jsonData];
}
}
else
{
NSLog(#"This Data can't be serialized");
}
//NSLog(#"URL Request %#",[request allHTTPHeaderFields]);
NSLog(#"jsonDATA %#",jsonData);
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
if (connectionError) {
//NSLog(#"Error %#",connectionError.description);
}else
{
NSLog(#"%#",response);
NSString *str = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"data str %#",str);
}
}];
The Contents of JSONstring are ==
{
"ScreenID" : "screenID1",
"DeviceID" : "E7EF8DCE-CE8A-4F0C-BBC5-F080C29FEF29",
"SessionStartTime" : "2014-03-27T06:50:15",
"SessionEndTime" : "2014-03-27T06:50:15"
}
The Contents of jsonDATA are ==
<7b0a2020 22536372 65656e49 4422203a 20224c61 6e64696e 67506167 65564322 2c0a2020 22446576 69636549 4422203a 20224537 45463844 43452d43 4538412d 34463043 2d424243 352d4630 38304332 39464546 3239222c 0a202022 53657373 696f6e53 74617274 54696d65 22203a20 22323031 342d3033 2d323754 30373a31 343a3336 222c0a20 20225365 7373696f 6e456e64 54696d65 22203a20 22323031 342d3033 2d323754 30373a31 343a3336 220a7d>
My Problem :-
since the format of HTTPBody in my webservice does not support the format generated by
[request setHTTPBody:jsonData];
however it would be ok if i could use
[request setHTTPBody:JSONstring];
but
the NSString argument can't be used with setHTTPBody method
What should i do ?
is there an alternative solution for this ?

Encoding the JSON string to data to set as the body data is the correct thing to do. It doesn't change the format or any of the string contents (your log of the data doesn't really mean anything in this form).
When the data gets to the server it will be used as a string, which is a JSON formatted string with a set of key/value pairs. This is expected behaviour.
If your server doesn't handle the JSON properly then you either have an issue with the headers that are set on the request or the keys/values that the JSON contains.

Related

NSMutableURLRequest returning JSON with empty sub-arrays

I have created a method that uses NSMutableURLRequest to request and receive JSON from a RESTful API running on a remote machine. The request successfully returns some JSON, but the returned sub-arrays in the JSON (see tasks: []) are empty.
The JSON returned from the API is:
{
"error":false,
"tasks":[
{
"id":1,
"task":"Get Milk",
"status":0,
"createdAt":"2014-08-09 12:29:15"
},
{
"id":2,
"task":"Call Mom",
"status":0,
"createdAt":"2014-08-09 12:46:52"
},
{
"id":3,
"task":"Call Dad",
"status":0,
"createdAt":"2014-08-09 12:47:04"
},
{
"id":4,
"task":"Study",
"status":0,
"createdAt":"2014-08-09 12:47:08"
}
]
}
The method that utilizies NSMutableURLRequest (proper parameters being passed is assumed) is:
-(NSDictionary *) apiRequestWithEndpoint:(NSString *) endpoint
withParams:(NSDictionary *) params
withHTTPHeaders:(NSDictionary *) headers
withHTTPMethod:(NSString *) method
{
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:endpoint]];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPMethod:method];
//set headers
for (id key in headers) {
[request setValue:[headers valueForKey:key] forHTTPHeaderField:key];
}
//set paramaters in request body
NSMutableString *requestBody = [[NSMutableString alloc] init];
int keyIndex = 0;
for (id key in params) {
if (keyIndex == 0) {
[requestBody appendFormat:#"%#=%#", key, [params valueForKey:key]];
} else {
[requestBody appendFormat:#"&%#=%#", key, [params valueForKey:key]];
}
keyIndex++;
}
[request setHTTPBody:[requestBody dataUsingEncoding:NSUTF8StringEncoding]];
NSURLResponse *response;
NSError *NSURLError = nil;
NSData *data = [NSURLConnection sendSynchronousRequest:request
returningResponse:&response
error:&NSURLError];
if (NSURLError) {
NSLog(#"Error: %# Cancelling operation.", NSURLError);
return nil;
}
NSError *NSJSONSerializationError = nil;
NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:data
options:kNilOptions
error:&NSJSONSerializationError];
if (NSJSONSerializationError) {
NSLog(#"Error: %# Cancelling operation.", NSJSONSerializationError);
return nil;
}
NSLog(#"Data: %#",[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);
return responseJSON;
}
Notice the 4th last line that logs the returned NSData from the NSMutableURLRequest, the output is:
Data: {"error":false "tasks":[]}
The code that calls the above method:
NSString *getAllTasksEndpoint = #"http://developmentVPS.com/TaskList-API/v1/tasks";
NSString *apiKey = #"A Valid API Key";
NSDictionary *headers = [[NSDictionary alloc] initWithObjectsAndKeys:apiKey, #"Authorization", nil];
NSDictionary *responseJSON = [self apiRequestWithEndpoint:getAllTasksEndpoint
withParams:nil
withHTTPHeaders:headers
withHTTPMethod:#"GET"];
It is my understanding that the entire data returned from the request should be logged in that NSLog call, but "tasks" is empty. I am new to iOS development, so I may be missing something simple. Does anybody see anything I am missing here?

NSURLConnection wrong order

I have a NSURLConnection (two of them), and they're running in the wrong order.
Here's my method:
- (void)loginToMistarWithPin:(NSString *)pin password:(NSString *)password {
NSURL *url = [NSURL URLWithString:#"https://mistar.oakland.k12.mi.us/novi/StudentPortal/Home/Login"];
//Create and send request
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:url];
[request setHTTPMethod:#"POST"];
NSString *postString = [NSString stringWithFormat:#"Pin=%#&Password=%#",
[self percentEscapeString:pin],
[self percentEscapeString:password]];
NSData * postBody = [postString dataUsingEncoding:NSUTF8StringEncoding];
[request setHTTPBody:postBody];
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
{
// do whatever with the data...and errors
if ([data length] > 0 && error == nil) {
NSError *parseError;
NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:data options:0 error:&parseError];
if (responseJSON) {
// the response was JSON and we successfully decoded it
NSLog(#"Response was = %#", responseJSON);
} else {
// the response was not JSON, so let's see what it was so we can diagnose the issue
NSString *loggedInPage = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"Response was not JSON (from login), it was = %#", loggedInPage);
}
}
else {
NSLog(#"error: %#", error);
}
}];
//Now redirect to assignments page
NSURL *homeURL = [NSURL URLWithString:#"https://mistar.oakland.k12.mi.us/novi/StudentPortal/Home/PortalMainPage"];
NSMutableURLRequest *requestHome = [[NSMutableURLRequest alloc] initWithURL:homeURL];
[request setHTTPMethod:#"POST"];
[NSURLConnection sendAsynchronousRequest:requestHome queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *homeResponse, NSData *homeData, NSError *homeError)
{
// do whatever with the data...and errors
if ([homeData length] > 0 && homeError == nil) {
NSError *parseError;
NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:homeData options:0 error:&parseError];
if (responseJSON) {
// the response was JSON and we successfully decoded it
NSLog(#"Response was = %#", responseJSON);
} else {
// the response was not JSON, so let's see what it was so we can diagnose the issue
NSString *homePage = [[NSString alloc] initWithData:homeData encoding:NSUTF8StringEncoding];
NSLog(#"Response was not JSON (from home), it was = %#", homePage);
}
}
else {
NSLog(#"error: %#", homeError);
}
}];
}
- (NSString *)percentEscapeString:(NSString *)string
{
NSString *result = CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault,
(CFStringRef)string,
(CFStringRef)#" ",
(CFStringRef)#":/?#!$&'()*+,;=",
kCFStringEncodingUTF8));
return [result stringByReplacingOccurrencesOfString:#" " withString:#"+"];
}
So, it's two NSURLConnection's that are added to the [NSOperationQueue mainQueue]. What my output is showing me is that the second NSURLConnection is running before the first one. So it tries to go to the page where I download data before I'm logged in, so it (obviously) returns a "You're not logged in" error.
How do I schedule them one after another?
The issue, as I suspect you have realized, is that you're doing asynchronous network requests (which is good; you don't want to block the main queue), so there's no assurance of the order they'll finish.
The quickest and easiest answer is to simply put the call to the second request inside the completion block of the first one, not after it. You don't want to be making that second one unless the first one succeeded anyway.
To keep your code from getting unwieldy, separate the login from the request for main page. And you can use the completion block pattern which is common with asynchronous methods. You add a parameter to loginToMistarWithPin that specifies what it should do when the request finishes. You might have one completion block handler for success, and one for failure:
- (void)loginToMistarWithPin:(NSString *)pin password:(NSString *)password success:(void (^)(void))successHandler failure:(void (^)(void))failureHandler {
NSURL *url = [NSURL URLWithString:#"https://mistar.oakland.k12.mi.us/novi/StudentPortal/Home/Login"];
//Create and send request
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:url];
[request setHTTPMethod:#"POST"];
NSString *postString = [NSString stringWithFormat:#"Pin=%#&Password=%#",
[self percentEscapeString:pin],
[self percentEscapeString:password]];
NSData * postBody = [postString dataUsingEncoding:NSUTF8StringEncoding];
[request setHTTPBody:postBody];
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
{
// do whatever with the data...and errors
if ([data length] > 0 && error == nil) {
NSError *parseError;
NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:data options:0 error:&parseError];
if (responseJSON) {
// the response was JSON and we successfully decoded it
NSLog(#"Response was = %#", responseJSON);
// assuming you validated that everything was successful, call the success block
if (successHandler)
successHandler();
} else {
// the response was not JSON, so let's see what it was so we can diagnose the issue
NSString *loggedInPage = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"Response was not JSON (from login), it was = %#", loggedInPage);
if (failureHandler)
failureHandler();
}
}
else {
NSLog(#"error: %#", error);
if (failureHandler)
failureHandler();
}
}];
}
- (void)requestMainPage {
//Now redirect to assignments page
NSURL *homeURL = [NSURL URLWithString:#"https://mistar.oakland.k12.mi.us/novi/StudentPortal/Home/PortalMainPage"];
NSMutableURLRequest *requestHome = [[NSMutableURLRequest alloc] initWithURL:homeURL];
[requestHome setHTTPMethod:#"GET"]; // this looks like GET request, not POST
[NSURLConnection sendAsynchronousRequest:requestHome queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *homeResponse, NSData *homeData, NSError *homeError)
{
// do whatever with the data...and errors
if ([homeData length] > 0 && homeError == nil) {
NSError *parseError;
NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:homeData options:0 error:&parseError];
if (responseJSON) {
// the response was JSON and we successfully decoded it
NSLog(#"Response was = %#", responseJSON);
} else {
// the response was not JSON, so let's see what it was so we can diagnose the issue
NSString *homePage = [[NSString alloc] initWithData:homeData encoding:NSUTF8StringEncoding];
NSLog(#"Response was not JSON (from home), it was = %#", homePage);
}
}
else {
NSLog(#"error: %#", homeError);
}
}];
}
Then, when you want to login, you can do something like:
[self loginToMistarWithPin:#"1234" password:#"pass" success:^{
[self requestMainPage];
} failure:^{
NSLog(#"login failed");
}];
Now, change those successHandler and failureHandler block parameters to include whatever data you need to pass back, but hopefully it illustrates the idea. Keep your methods short and tight, and use completion block parameters to specify what an asynchronous method should do when it's done.
Can you check the below link. It is about forcing one operation to wait for another.
NSOperation - Forcing an operation to wait others dynamically
Hope this helps.

JSON and XML Wrapper for Parsing in iOS

I have seen that most data in iOS is in either JSON or XML. I was interested to know whether there is any third party library or wrapper class that tackles both types of data and responses accordingly. I know I could use for example JSONKit for JSON data and NSXMLParser for XML. But i looking for one that tackles both.
Is there any such wrapper?
Welcome to any suggestions and guidance. Thanks.
I think It's support to JSON /XML,just can you change some line.
NSString *str1=#"type url";
NSString *poststr1 = [NSString stringWithFormat:#"%#",str1];
NSString *posturl1=[NSString stringWithFormat:#" your url json/xml"];
// NSLog(#"city url name %#",posturl1);
NSURL *url=[NSURL URLWithString:[NSString stringWithFormat:#"%#",posturl1]];
NSData *postData1 = [poststr1 dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData1 length]];
NSMutableURLRequest *request =[[[NSMutableURLRequest alloc] init] autorelease];
[request setHTTPBody:postData1];
[request setURL:url];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
NSError *error;
NSURLResponse *response;
NSData *urlData=[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
// NSString *data=[[NSString alloc]initWithData:urlData encoding:NSUTF8StringEncoding];//this line supprted to json
NSDictionary* json = [NSJSONSerialization
JSONObjectWithData:urlData
options:kNilOptions
error:&error];//this line supported to xml
NSLog(#"json %#",json);
//NSDictionary*results = [data JSONValue];//this line supported to JSON
//NSLog(#"results json----->%#",results);
AFNetworking will do both, and has a goot reputation, for example see the Ray Wenderlich site which has lots of other useful information too.
I have created one wrapper class for json. In there, I have created one method given below, I think it will help you.
Parse Method:
-(void)jsonDeserialize:(NSString *)key fromDict:(id)content completionHandler:(void (^) (id parsedData, NSDictionary *fromDict))completionHandler{
if (key==nil && content ==nil) {
completionHandler(nil,nil);
}
if ([content isKindOfClass:[NSArray class]]) {
for (NSDictionary *obj in content) {
[self jsonDeserialize:key fromDict:obj completionHandler:completionHandler];
}
}
if ([content isKindOfClass:[NSDictionary class]]) {
id result = [content objectForKey:key];
if ([result isKindOfClass:[NSNull class]] || result == nil) {
NSDictionary *temp = (NSDictionary *)content;
NSArray *keys = [temp allKeys];
for (NSString *ikey in keys) {
[self jsonDeserialize:key fromDict:[content objectForKey:ikey] completionHandler:completionHandler];
}
}else{
completionHandler(result,content);
}
}
}
Method Call:
NSData *content = [NSData dataWithContentsOfFile:[[NSBundle mainBundle]pathForResource:#"Sample" ofType:#"json"]];
NSError *error;
//to get serialized json data...
id dictionary = [NSJSONSerialization JSONObjectWithData:content options:NSJSONReadingMutableContainers error:&error];
//get data for key called GetInfo
[self jsonDeserialize:#"GetInfo" fromDict:dictionary completionHandler:^(id parsedData, NSDictionary *fromDict) {
NSLog(#"%# - %#",parsedData,fromDict);
}];

ios parsing json result after http request

am starting to build login form reading from external server via http request i need to parse json result to get user name
- (IBAction)getlogin:(UIButton *)sender {
NSString *rawStrusername = [NSString stringWithFormat:#"username=%#",_username.text];
NSString *rawStrpassword = [NSString stringWithFormat:#"password=%#",_password.text];
NSString *post = [NSString stringWithFormat:#"%#&%#", rawStrusername, rawStrpassword];
// NSString *post = #"rawStrusername&rawStrpassword";
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
/* NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]]; */
NSURL *url = [NSURL URLWithString:#"http://www.othaimmarkets.com/my_services_path/user/login.json"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setHTTPMethod:#"POST"];
/* [request setValue:postLength forHTTPHeaderField:#"Content-Length"]; */
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
NSURLResponse *response;
NSError *err;
NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&err];
NSLog(#"responseData: %#", [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding]);
//NSLog(#"responseData: %#", responseData);
}
I get this result:
{"sessid":"g2ev7til6d750ducrkege0cbj2","session_name":"SESS02795057fe9e6b2fc0777bf4057b248f","user":{"uid":"617","name":"mohammed.abdelrasoul#gmail.com","mail":"mohammed.abdelrasoul#gmail.com","mode":"0","sort":"0","threshold":"0","theme":"","signature":"","signature_format":"0","created":"1316602317","access":"1352643854","login":"1352666338","status":"1","timezone":"10800","language":"ar","picture":"","init":"mohammed.abdelrasoul#gmail.com","data":"a:5:{s:18:\"country_iso_code_2\";s:2:\"SA\";s:13:\"timezone_name\";s:11:\"Asia/Riyadh\";s:5:\"block\";a:1:{s:7:\"webform\";a:1:{s:15:\"client-block-88\";i:1;}}s:13:\"form_build_id\";s:37:\"form-3ae73833f08accc7abe5517347ea87eb\";s:7:\"contact\";i:0;}","country_iso_code_2":"SA","timezone_name":"Asia/Riyadh","block":{"webform":{"client-block-88":1}},"form_build_id":"form-3ae73833f08accc7abe5517347ea87eb","contact":0,"roles":{"2":"authenticated user"}}}
Or, formatted for the sake of legibility:
{
"sessid":"g2ev7til6d750ducrkege0cbj2",
"session_name":"SESS02795057fe9e6b2fc0777bf4057b248f",
"user":{
"uid":"617",
"name":"mohammed.abdelrasoul#gmail.com",
"mail":"mohammed.abdelrasoul#gmail.com",
"mode":"0",
"sort":"0",
"threshold":"0",
"theme":"",
"signature":"",
"signature_format":"0",
"created":"1316602317",
"access":"1352643854",
"login":"1352666338",
"status":"1",
"timezone":"10800",
"language":"ar",
"picture":"",
"init":"mohammed.abdelrasoul#gmail.com",
"data":"a:5:{s:18:\"country_iso_code_2\";s:2:\"SA\";s:13:\"timezone_name\";s:11:\"Asia/Riyadh\";s:5:\"block\";a:1:{s:7:\"webform\";a:1:{s:15:\"client-block-88\";i:1;}}s:13:\"form_build_id\";s:37:\"form-3ae73833f08accc7abe5517347ea87eb\";s:7:\"contact\";i:0;}",
"country_iso_code_2":"SA",
"timezone_name":"Asia/Riyadh",
"block":{
"webform":{
"client-block-88":1
}
},
"form_build_id":"form-3ae73833f08accc7abe5517347ea87eb",
"contact":0,
"roles":{
"2":"authenticated user"
}
}
}
how i can get the objects data or parse the result to get user name
any help or examples will be appreciated
You need to use the NSJSONSerialization class method, JSONObjectWithData:options:error: to create an NSDictionary:
NSError *error;
NSDictionary *jsonDict = [NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableContainers error:&error];
if (! error) {
NSLog(#"%#",jsonDict);
}else{
NSLog(#"%#",error.localizedDescription);
}
This will get you to the point where you can look at the dictionary, which will be easier to read. It looks like you need to use objectForKey:#"sessid" to get you to user, then objectForKey#"user", then objectForKey:#"name" to get you to the name.
Check out this framework for parsing json. https://github.com/stig/json-framework/
Also check out this answer iPhone/iOS JSON parsing tutorial. You'll find a link to a tutorial you can do to get acquainted with json parsing in ios.
See this answer and some code :
NSMutableData *data; // Contains data received from the URL connection declares in header
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)dataIn
{
// Do it this way because connection doesn't guarantee all the data is in
POLLog(#" Tide View connection");
[data appendData:dataIn];
}
- (void) connectionDidFinishLoading:(NSURLConnection *) conn
{
NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSDictionary *results = [jsonString JSONValue]; // This is a new category added to the NSString by SBJSON
//100 parameters
for (int n=0;n<=100;n++)
{
// Get all the returned results
params[n] = [[results objectForKey:[NSString stringWithFormat:#"param%d",n]] floatValue];
}
To expand upon rdelmar's answer (which I think you should accept), you can use NSJSONSerialization and then navigate the NSDictionary results to extract the userName:
NSError *error;
NSDictionary *jsonDict = [NSJSONSerialization JSONObjectWithData:responseData
options:0
error:&error];
if (error == nil) {
NSDictionary *userDictionary = [jsonDict objectForKey:#"user"];
NSString *userName = [userDictionary objectForKey:#"name"];
// do what you need with the userName
} else {
NSLog(#"%#",error.localizedDescription);
}
Or if using the latest version of Xcode, you can replace those objectForKey references with the even more concise Modern Objective-C syntax:
NSDictionary *userDictionary = jsonDict[#"user"];
NSString *userName = userDictionary[#"name"];

Convert JSON feed to NSDictionary

Where JSON_CATEGORY_DATA_URL_STRING is my feed URL, which returns fine as:
[
{
"group":"For Sale",
"code":"SSSS"
},
{
"group":"For Sale",
"category":"Wanted",
"code":"SWNT"
}
]
I cannot seem to get a nice NSDictionary (or NSArray) out of the following code:
+ (NSDictionary *)downloadJSON
{
NSDictionary *json_string;
NSString *dataURL = [NSString stringWithFormat:#"%#", JSON_CATEGORY_DATA_URL_STRING];
NSLog(#"%#",dataURL);
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:dataURL]];
NSData *response = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
json_string = [[[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding]autorelease];
NSDictionary *json_dict = (NSDictionary *)json_string;
NSLog(#"json_dict\n%#",json_dict);
NSLog(#"json_string\n%#",json_string);
return json_string;
}
I've read many posts on this, but am not getting it.
With IOS5 you can use NSJSONSerialization for serializing the JSON.
NSDictionary *dictionary = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:&error];
You can't just cast a string as a dictionary and expect it to parse the JSON. You must use a JSON parsing library to take that string and convert it into a dictionary.
I made a class that makes this task easier. It uses iOS 5's NSJSONSerialization. Clone it from github here.
You need to use JSON parser. here is the edited code
+ (NSDictionary *)downloadJSON
{
NSDictionary *json_string;
NSString *dataURL = [NSString stringWithFormat:#"%#", JSON_CATEGORY_DATA_URL_STRING];
NSLog(#"%#",dataURL);
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:dataURL]];
NSData *response = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
json_string = [[[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding]autorelease];
//JSONValue is a function that will return the appropriate object like dictionary or array depending on your json string.
NSDictionary *json_dict = [json_string JSONValue];
NSLog(#"json_dict\n%#",json_dict);
NSLog(#"json_string\n%#",json_string);
return json_dict;
}
this should be the code to get the NSDictionary. but you json string is an array so instead use .
+ (NSArray *)downloadJSON
{
NSDictionary *json_string;
NSString *dataURL = [NSString stringWithFormat:#"%#", JSON_CATEGORY_DATA_URL_STRING];
NSLog(#"%#",dataURL);
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:dataURL]];
NSData *response = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
json_string = [[[NSString alloc] initWithData:response encoding:NSUTF8StringEncoding]autorelease];
NSArray *json_dict = [json_string JSONValue];
NSLog(#"json_dict\n%#",json_dict);
NSLog(#"json_string\n%#",json_string);
return json_dict;
}
Edit:
you need to use JSON.framework to call JSONValue method.
also you need to return json_dict instead of json_string as json_string is of NSString type and not NSDictionary or NSArray.
and dont autorelease it, as it is your class variable
create method to fetchjson data.Pass your url in urlwithstring.
-(void)fetchjsondata
{
NSString *login= [[NSString stringWithFormat:#"your url string"]stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSLog(#"----%#", login);
NSURL *url = [NSURL URLWithString:[login stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
//-- Get request and response though URL
NSMutableURLRequest *request = [[NSMutableURLRequest alloc]initWithURL:url];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
dispatch_async(dispatch_get_main_queue(), ^{
if (data) {
dic_property= [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
NSLog(#"%#", dic_property);
NSLog(#"counts=%d",[[dic_property objectForKey:#"Data"]count]);
}
else {
NSLog(#"network error, %#", [error localizedFailureReason]);
}
});
}];
}
call fetchjsonmethod in anywhere.
[NSThread detachNewThreadSelector:#selector(fetchdata) toTarget:self withObject:nil];

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