How to get the time zone name for a CLLocation

问题:

I have an application that uses a CLGeocoder to forwardGeocode a placemark from an address string. The CLPlacemark response contains a CLLocation which gives me GPS coordinates.

The only way to create an NSTimeZone seems to be by using the correct Time Zone Name. It is important to point out that I am not using the current location of the device, so [NSTimeZone localTimeZone] will not work for me.

Is there a way to get the timezone name for the CLLocation so that I can create an NSTimeZone correctly?

NOTE: I have been using timeZoneForSecondsFromGMT but that never contains correct DST data, so it is not helpful for me.

回答1:

You should use https://github.com/Alterplay/APTimeZones to get NSTimeZone from CLLocation. It also works with CLGeocoder.

回答2:

since iOS9 it should be possible direclty using CLGeocoder as specified here: https://developer.apple.com/library/prerelease/ios/releasenotes/General/WhatsNewIniOS/Articles/iOS9.html

Search results for MapKit and CLGeocoder can provide a time zone for the result.

回答3:

I found an interesting approach using CLGeocoder, which I put into a category on CLLocation. The interesting part looks like this:

-(void)timeZoneWithBlock:(void (^)(NSTimeZone *timezone))block {        
    [[[CLGeocoder alloc] init] reverseGeocodeLocation:self completionHandler:^(NSArray *placemarks, NSError *error) {           
        NSTimeZone *timezone = nil;

        if (error == nil && [placemarks count] > 0) {               
            CLPlacemark *placeMark = [placemarks firstObject];
            NSString *desc = [placeMark description];

            NSRegularExpression  *regex  = [NSRegularExpression regularExpressionWithPattern:@"identifier = \"([a-z]*\\/[a-z]*_*[a-z]*)\"" options:NSRegularExpressionCaseInsensitive error:nil];
            NSTextCheckingResult *result = [regex firstMatchInString:desc options:0 range:NSMakeRange(0, [desc length])];

            NSString *timezoneString = [desc substringWithRange:[result rangeAtIndex:1]];

            timezone = [NSTimeZone timeZoneWithName:timezoneString];
        }
        block(timezone);            
    }];
}

Usage is like this:

CLLocation *myLocation = ...
[myLocation timeZoneWithBlock:^(NSTimeZone *timezone) {
    if (timezone != nil) {
        // do something with timezone
    } else {
        // error determining timezone
    }
}];

Despite requiring a network connection and working asynchronously, I have found this to be the most reliable way of getting the time zone for a location.

回答4:

I got the proper solution for the getting the timezone name from CLLocation but it works for ios8 and higher version than it. Click on the link for see the answer of the same question like this for getting time zone.