在flutter dart中搜索特定字段的firebase文档并将其存储

【问题标题】：search firebase document for a specific field in flutter dart and store it在flutter dart中搜索特定字段的firebase文档并将其存储
【发布时间】：2021-11-05 11:49:02
【问题描述】：

我正在尝试恢复其字段“电子邮件”等于某个值的文档我的代码没有得到任何东西不知道是什么问题

 void EditDisplayedName(String email, String name) async {
  CollectionReference s = FirebaseFirestore.instance
      .collection("Users")
      .doc("list_instructors")
      .collection("Instructor")
    ..where("Email", isEqualTo: email);

  s.doc(email).update({'Full Name': name});
} //end method

【问题讨论】：

标签： firebase flutter dart google-cloud-firestore

【解决方案1】：

您的代码尚未找到/读取电子邮件地址的文档。

正确的流程是：

// 1. Create a reference to the collection
CollectionReference s = FirebaseFirestore.instance
    .collection("Users")
    .doc("list_instructors")
    .collection("Instructor")

// 2. Create a query for the user with the given email address
Query query = s.where("Email", isEqualTo: email);

// 3. Execute the query to get the documents
QuerySnapshot querySnapshot = await query.get();

// 4. Loop over the resulting document(s), since there may be multiple
querySnapshot.docs.forEach((doc) {

  // 5. Update the 'Full Name' field in this document
  doc.reference.update({'Full Name': name});
});

【讨论】：