Question

我到处寻找，似乎无法找到解决方案。我正在使用ASIHTTPRequest在我的iOS应用程序中使用FourSquare API。但是，当我尝试打印我希望返回给我的JSON字符串时，我得到“null”。如果我在浏览器中导航到同一个请求URL，我会得到一大堆JSON。这是我的代码......

- (void)fetchFoursquareLocationsUsingLocation:(CLLocation *)location {
// First, let's build our request
CLLocationDegrees latitude = location.coordinate.latitude;
CLLocationDegrees longitude = location.coordinate.longitude;
NSString *foursquareURLString = [NSString stringWithFormat:@"https://api.foursquare.com/v2/venues/search?ll=%0.6f,%0.6f&client_id=%@&client_secret=%@&v=20120103", 
                                 latitude,
                                 longitude,
                                 FOURSQUARE_CLIENT_ID, 
                                 FOURSQUARE_CLIENT_SECRET];

ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:foursquareURLString]];
self.foursquareData = [[NSMutableData alloc] init];

request.delegate = self;
[request startAsynchronous];
}

#pragma mark - ASIHTTPRequest Delegate
- (void)request:(ASIHTTPRequest *)request didReceiveData:(NSData *)data {
[self.foursquareData appendData:data];

}

- (void)requestFinished:(ASIHTTPRequest *)request {
NSString *jsonCheck = [[NSString alloc] initWithData:self.foursquareData encoding:NSUTF8StringEncoding];

NSLog(@"%@", jsonCheck);
}

更新：感谢@ Kamarshad的SO帖子How to get Venues list Using FourSquare Api，我能够获得有效的JSON。不同之处在于我以异步方式提出请求

NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:foursquareURLString]];
NSOperationQueue *queue = [[NSOperationQueue alloc] init];

[NSURLConnection sendAsynchronousRequest:request 
                                   queue:queue 
                       completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
    //
    if (error != nil) {
        NSLog(@"Something went wrong...%@", [error localizedDescription]);
    }
    else {
        NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
        NSLog(@"%@", jsonString);
    }
}];

ASIHTTPRequest是什么让有效的回复无法回来？

Answer 1

这是因为您没有正确地传递V(date)值，而请求您只是传递静态（旧），这可能在该日期之后无效。您必须在URL字符串中传递更新（当前）V(date)，V应该是您正在向FourSquare发出请求的CurrentDate。

尝试使用以下代码并再次使用。

更新：一件事您应该传递一些东西进行搜索因为在您的请求中您没有传递任何搜索查询

NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc]init] autorelease];
[dateFormatter setDateFormat:@"YYYYMMdd"];
NSString *dateString = [dateFormatter stringFromDate:currDate];
//dateString it;s used for being UpTodate for API request
NSString* rest=@"street"
// To be Search

MakeRequest As Below和Code的其余部分将与您使用的相同。

NSString *foursquareURLString = [NSString stringWithFormat:@"https://api.foursquare.com/v2/venues/search?ll=%0.6f,%0.6f&client_id=%@&client_secret=%@&v=%@&query=%@", 
                             latitude,
                             longitude,
                             FOURSQUARE_CLIENT_ID, 
                             FOURSQUARE_CLIENT_SECRET,dateString,rest];
//Convert the Special characters into escapes. 

 foursquareURLString =[foursquareURLString  stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
 ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:foursquareURLString]];
 //Rest will be same

For More Detail About the FourSquare API endpoints go Through This Link

我希望它能给你正确的结果而不是Null !!!!!!!。

FourSquare请求在iOS中返回空字符串

1 个答案: