在Firebase云功能中获取null值onDelete()

时间:2017-07-15 11:54:55

标签: firebase firebase-realtime-database firebase-storage

我在onDelete()firebase云功能中获得null值。以下是我的代码

 exports.jobSeekerToES=functions.database.ref('/Users/{userId}/userFileDetails/files/{fileKey}').onDelete(event=>
{

var file=event.data.val();
console.log("deleted file key"+event.params.fileKey);
console.log("deleted file "+file);  // file is null

});

它在日志上打印fileKey。但文件为空 请帮助我,我错了

1 个答案:

答案 0 :(得分:14)

event.data.val()在删除后返回位置的值。对于onDelete()触发器,它总是为空。要在删除之前获取值,请使用事件快照的previous属性:

exports.jobSeekerToES=functions.database.ref(
    '/Users/{userId}/userFileDetails/files/{fileKey}').onDelete(event=>
{

  var file=event.data.previous.val();  // <= CHANGED
  console.log("deleted file key"+event.params.fileKey);
  console.log("deleted file "+file);

});