How to convert NSArray of NSStrings into Json String iOS - ios

Question

I have an Array of Roll Numbers
NSArray *rollArray = [NSArray arrayWithObjects:#"1", #"22", #"24", #"11", nil];
I need to send this array in a Web Service request
whose format is like this (in JSON format)
JSON data
{
"existingRoll":["22","34","45","56"], // Array of roll numbers
"deletedRoll":["20","34","44","56"] // Array of roll numbers
}
but I am facing problem in converting Array of Roll numbers (rollArray) into json String
in the desired format.
I am trying this
NSMutableDictionary *postDict = [[NSMutableDictionary alloc]init];
[postDict setValue:[rollArray componentsJoinedByString:#","] forKey:#"existingRoll"];
NSString *str = [Self convertToJSONString:postDict]; // converts to json string
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:str options:0 error:nil];
[request setHTTPBody:jsonData];
I am using iOS 7

Answer 1

There is no need to use the following code snippets:
[rollArray componentsJoinedByString:#","]
NSString *str = [Self convertToJSONString:postDict];
You can create JSON by using the following code:
NSArray *rollArray = [NSArray arrayWithObjects:#"1", #"22", #"24", #"11", nil];
NSMutableDictionary *postDict = [[NSMutableDictionary alloc]init];
[postDict setValue:rollArray forKey:#"existingRoll"];
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:postDict options:0 error:nil];
// Checking the format
NSLog(#"%#",[[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding]);

Answer 2

Try this :
NSDictionary *object = #{
#"existingRoll":#[#"22",#"34",#"45",#"56"],
#"deletedRoll":#[#"20",#"34",#"44",#"56"]
};
if ([NSJSONSerialization isValidJSONObject:object]) {
NSData* data = [ NSJSONSerialization dataWithJSONObject:object options:NSJSONWritingPrettyPrinted error:nil ];
NSString *str = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(str);
}

Answer 3

NSMutableDictionary *postDict = [[NSMutableDictionary alloc] init];
[postDict setValue:#"Login" forKey:#"methodName"];
[postDict setValue:#"admin" forKey:#"username"];
[postDict setValue:#"12345" forKey:#"password"];
[postDict setValue:#"mobile" forKey:#"clientType"];
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:postDict options:0 error:nil];
// Checking the format
NSString *urlString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
// Convert your data and set your request's HTTPBody property
NSString *stringData = [[NSString alloc] initWithFormat:#"jsonRequest=%#", urlString];
//#"jsonRequest={\"methodName\":\"Login\",\"username\":\"admin\",\"password\":\"12345\",\"clientType\":\"web\"}";
NSData *requestBodyData = [stringData dataUsingEncoding:NSUTF8StringEncoding];

Answer 4

You can use following method to get Json string from any type of NSArray :
NSArray *rollArray = [NSArray arrayWithObjects:#"1", #"22", #"24", #"11", nil];
NSData *data = [NSJSONSerialization dataWithJSONObject:rollArray options:0 error:nil];
NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"Json string is: %#", jsonString);