Question

我正在开发一款游戏，可将两个玩家与Firebase实时数据库连接起来。但是我想要一种可以在玩家与互联网失去连接时删除其数据的方法。

Answer 1

这可以通过OnDisconnect方法进行更新。

This original answer from Frank最初描述了OnDisconnect方法的更多细节。

您可以使用this Firebase example设置“已连接状态”，该功能使用带有OnDisconnect的实时数据库和云功能来显示用户状态。从示例中拉出：

var userStatusDatabaseRef = firebase.database().ref('/status/' + uid);

firebase.database().ref('.info/connected').on('value', function(snapshot) {
    // If we're not currently connected, don't do anything.
    if (snapshot.val() == false) {
        return;
    };

    // If we are currently connected, then use the 'onDisconnect()'
    // method to add a set which will only trigger once this
    // client has disconnected by closing the app,
    // losing internet, or any other means.
    userStatusDatabaseRef.onDisconnect().set(isOfflineForDatabase).then(function() {
        // The promise returned from .onDisconnect().set() will
        // resolve as soon as the server acknowledges the onDisconnect()
        // request, NOT once we've actually disconnected:
        // https://firebase.google.com/docs/reference/js/firebase.database.OnDisconnect

        // We can now safely set ourselves as 'online' knowing that the
        // server will mark us as offline once we lose connection.
        userStatusDatabaseRef.set(isOnlineForDatabase);
    });
});

客户端断开连接时如何从Firebase Realtime数据库中删除数据

1 个答案: