推送后创建的对象的获取密钥(Angular和Firebase) [英] Get Key for object created after Push (Angular and Firebase)

问题描述

我在了解如何使用Firebase时遇到问题.我编写了一个函数来在Firebase数据库中推送一些数据.将数据推入数据库后，我需要获取生成的密钥.

I'm having problems understanding how to use Firebase. I wrote a function to push some data in my firebase database. I need to get the Key generated after I push the data into my db.

这是我的职责

  postData(order: orderInfo) {
    let uid = firebase.auth().currentUser.uid;
    this.db.list('transactions').push({
      currency: order.currency,
      total: order.total,
      rate: order.rate,
      uid: uid
    });
    console.log(order.$key);
    this.db.list('transactionsPerUser').update(uid, order.$key);
  }

当我将数据推送到事务处理路径时，它还会推送用户uid，因此我可以将数据从我的用户数据库链接到事务处理数据库.我现在想要的是在数据库的其他部分链接用户进行的交易，如下所示:

When I push the data to transactions path, it also pushes user uid so I can link the data from my user database to transactions database. What I want now is to link in other part of my database the transactions made by users, something like this:

transactionsPerUser {
     user1 {
           order.$key (key generated by push) : "true"
                     }
            {

如您所见，我正在尝试console.log(order.$ key)，但它返回未定义.我该如何解决?其次，这是构建数据库的正确方法吗?感谢您的帮助！

As you can see, I'm trying to console.log(order.$key) but it returns undefined. How can I solve this?? and second, is this a proper way to structure my database? Thanks for your help!

推荐答案

我将对邮寄行进行少量更改，并在交易中添加/

I would make a small change to the post line and add / to the transactions

postData(order: orderInfo) {
    let uid = firebase.auth().currentUser.uid;

// Change this next line to save the transaction

    var newRef = this.db.list('/transactions').push({
      currency: order.currency,
      total: order.total,
      rate: order.rate,
      uid: uid
    });

// get just the key reference
var newKey= newRef.key;

//then change this refer

    console.log(newKey);

//To update you would change the next line

    this.db.list('transactionsPerUser').update(newKey, order.newInfo);
}

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