NSString *path = [[NSBundle mainBundle] pathForResource:@"business_city" ofType:@"json"];
NSLog(@"path:%@",path);
NSData *jdata = [[NSData alloc] initWithContentsOfFile:path ];
NSLog(@"length:%d",[jdata length]);
NSError *error = nil;
NSArray * Adata = [NSJSONSerialization JSONObjectWithData:jdata options:kNilOptions error:&error];