I'm having a problem with NSJSONSerialization reading JSON from the Met Office Datapoint API.
I get the following error
Error Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be completed. (Cocoa error 3840.)" (Unable to convert data to string around character 58208.
I have checked and think this is the offending line according to the character position
{"id":"353556","latitude":"57.1893","longitude":"-5.0929","name":"Sóil Chaorainn"}
The JSON itself appears to be valid according to a couple of Validators I tried, and I would expect it too be from a large organisation such as Met Office.
Shouldn't NSJSONSerialization work fine with characters such as 'ó'?
If not how do I go about changing the encoding type to deal with this?
Many Thanks in Advance
The Met Office Datapoint sends back data in ISO-8859-1 which isn't one of the supported data format for NSJSONSerialization.
To make it work create a string from the URL content at first with NSISOLatin1StringEncoding and then create the NSData you want to use in the NSJSONSerialization with a NSUTF8 encoding.
The following works to create the corresponding json object
NSError *error;
NSString *string = [NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://datapoint.metoffice.gov.uk/public/data/val/wxfcs/all/json/sitelist?key=<YOUR_API_KEY"] encoding:NSISOLatin1StringEncoding error:&error];
NSData *metOfficeData = [string dataUsingEncoding:NSUTF8StringEncoding];
id jsonObject = [NSJSONSerialization JSONObjectWithData:metOfficeData options:kNilOptions error:&error];
if (error) {
//Error handling
} else {
//use your json object
NSDictionary *locations = [jsonObject objectForKey:@"Locations"];
NSArray *location = [locations objectForKey:@"Location"];
NSLog(@"Received %d locations from the DataPoint", [location count]);
}
What is encoding for the JSON? JSON is supposed to UTF-8 but I have seen lousy APIs where they use ISO-8859-1. NSJSONSerialization only works UTF-8, UTF-16LE, UTF-16BE, UTF-32LE, UTF-32BE.
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