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Javascript 添加、更改和删除Firebase JS子项_Javascript_Firebase_Firebase Realtime Database - Fatal编程技术网

Javascript 添加、更改和删除Firebase JS子项

Javascript 添加、更改和删除Firebase JS子项,javascript,firebase,firebase-realtime-database,Javascript,Firebase,Firebase Realtime Database,我添加了child\u功能,但当删除或更改某些内容时,它不会自动更新。 如何在一个函数中添加、删除和更改子项 谢谢您是否尝试过“移除儿童”活动?对这四个事件中的每一个使用事件侦听器是正常的;添加、更改、移动和删除,而不是合并 听起来你在找这样的东西: function handleEvent(event, snapshot, optionalPreviousChildKey) { switch (event) { case "child_added": ... break

我添加了
child\u
功能,但当删除或更改某些内容时,它不会自动更新。 如何在一个函数中添加、删除和更改子项

谢谢

您是否尝试过“移除儿童”活动?对这四个事件中的每一个使用事件侦听器是正常的;添加、更改、移动和删除,而不是合并


听起来你在找这样的东西:

function handleEvent(event, snapshot, optionalPreviousChildKey) {
  switch (event) {
    case "child_added": ...
      break;
    ...
  }
}
ref.on("child_added", function(snapshot, previousChildKey) { handleEvent("child_added", snapshot, previousChildKey); })
ref.on("child_changed", function(snapshot, previousChildKey) { handleEvent("child_changed", snapshot); })
ref.on("child_moved", function(snapshot, previousChildKey) { handleEvent("child_moved", snapshot, previousChildKey); })
ref.on("child_removed", function(snapshot) { handleEvent("child_removed", snapshot); })