图片合并pdf

NSString *httpUrl = @"https://api-v2.1dq.com/v1/MergeImages2Pdf.json";
NSString *httpArg = @"";
[self request: httpUrl withHttpArg: httpArg];

-(void)request: (NSString*)httpUrl withHttpArg: (NSString*)HttpArg  {
    NSString *urlStr = [[NSString alloc]initWithFormat: @"%@?%@", httpUrl, HttpArg];
    NSURL *url = [NSURL URLWithString: urlStr];
    NSMutableURLRequest *request = [[NSMutableURLRequest alloc]initWithURL: url cachePolicy: NSURLRequestUseProtocolCachePolicy timeoutInterval: 10];
    [request setHTTPMethod: @"GET"];
    [NSURLConnection sendAsynchronousRequest: request
        queue: [NSOperationQueue mainQueue]
        completionHandler: ^(NSURLResponse *response, NSData *data, NSError *error){
            if (error) {
                NSLog(@"Httperror: %@%ld", error.localizedDescription, error.code);
            } else {
                NSInteger responseCode = [(NSHTTPURLResponse *)response statusCode];
                NSString *responseString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
                NSLog(@"HttpResponseCode:%ld", responseCode);
                NSLog(@"HttpResponseBody %@",responseString);
            }
        }];
}