我一整天都在尝试将 firebase 数据存储到数组中并打印出来，但无济于事。我将非常感谢社区的帮助。
下图是当前 firebase 数据库的样子:
下面是从 firebase 读取数据的函数代码:
- (void)readDataFromServer {
_ref = [[FIRDatabase database] reference];
_hotelRef = [_ref child:@"hotel bookings"];
NSString *userID = [FIRAuth auth].currentUser.uid;
FIRDatabaseQuery *userHotelBookingsQuery = [[_hotelRef child:userID] queryOrderedByChild:@"number"];
[userHotelBookingsQuery observeSingleEventOfType:FIRDataEventTypeValue withBlock:^(FIRDataSnapshot * _Nonnull snapshot) {
if (snapshot.value == [NSNull null]) {
NSLog(@"No messages");
} else {
[self.arrayOfBookingDetail removeAllObjects];
self.arrayOfBookingDetail = (snapshot.value);
NSString *firstMessage = [self.arrayOfBookingDetail objectAtIndex:0];
NSLog(@"First message is: %@", firstMessage);
}
}];
}
最佳答案
您的代码失败是因为您通过用户 uid 获得了实际上并不存在的 child 。 K2xxxxxxxx 是每个元素的唯一字符串，不对应于用户 ID。试试这个
_ref = [[FIRDatabase database] reference];
_hotelRef = [_ref child:@"hotel bookings"];
FIRDatabaseQuery *userHotelBookingsQuery = [_hotelRef queryOrderedByChild:@"number"];
[userHotelBookingsQuery observeSingleEventOfType:FIRDataEventTypeValue withBlock:^(FIRDataSnapshot * _Nonnull snapshot) {
if (snapshot.value == [NSNull null]) {
NSLog(@"No messages");
} else {
//[self.arrayOfBookingDetail removeAllObjects];
//self.arrayOfBookingDetail = (snapshot.children);
//NSString *firstMessage = [self.arrayOfBookingDetail objectAtIndex:0];
//NSLog(@"First message is: %@", firstMessage);
NSDictionary *allUsersData = (NSDictionary*)snapshot.value;
for (NSString *key in allUsersData.allKeys) {
NSLog("@key is %@, data is %@",key,allUsersData[key]);
}
}
}];
}
编辑:
要查询特定用户 - 将您的查询更改为
FIRDatabaseQuery *userHotelBookingsQuery = [[_hotelRef queryOrderedByChild:@"userID"] queryEqualToValue:@"GEmxxxxxxxxx"];
关于ios - 如何将 Firebase 数据存储在数组中并打印出来？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/37652564/