firebase - 如何将数据从Firebase存储到Model类:Flutter

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我想将数据作为List存储到我的Model类中，这是我的Model类代码

class BookingList {

  String bookingId;
  String userId;
  String vendorId;
  String mealName;
  String vendorName;
  String timestamp;
  bool paymentStatus;
  int mealPrice;

  BookingList(this.bookingId, this.userId, this.vendorId, this.mealName,
      this.vendorName, this.timestamp, this.paymentStatus, this.mealPrice);
}

Firebase数据库如下所示

谁能帮我？
提前致谢...

最佳答案

首先，您必须使用fromJson函数创建模型类，该函数将json转换为模型类。我为您准备了类(class)。您也可以从这里https://javiercbk.github.io/json_to_dart/

class BookingList {
  String bookingId;
  String userId;
  String vendorId;
  String mealName;
  String timestamp;
  bool paymentStatus;
  int mealPrice;

  BookingList(
      {this.bookingId,
      this.userId,
      this.vendorId,
      this.mealName,
      this.timestamp,
      this.paymentStatus,
      this.mealPrice});

  BookingList.fromJson(Map<String, dynamic> json) {
    bookingId = json['bookingId'];
    userId = json['userId'];
    vendorId = json['vendorId'];
    mealName = json['mealName'];
    timestamp = json['timestamp'];
    paymentStatus = json['paymentStatus'];
    mealPrice = json['mealPrice'];
  }

  Map<String, dynamic> toJson() {
    final Map<String, dynamic> data = new Map<String, dynamic>();
    data['bookingId'] = this.bookingId;
    data['userId'] = this.userId;
    data['vendorId'] = this.vendorId;
    data['mealName'] = this.mealName;
    data['timestamp'] = this.timestamp;
    data['paymentStatus'] = this.paymentStatus;
    data['mealPrice'] = this.mealPrice;
    return data;
  }
}

然后，您必须解析Firebase中的数据。

Future<List<BookingList>> getAllData() async {
    print("Active Users");
    var val = await fireStore
        .collection("booking")
        .getDocuments();
    var documents = val.documents;
    print("Documents ${documents.length}");
    if (documents.length > 0) {
      try {
        print("Active ${documents.length}");
        return documents.map((document) {
          BookingList bookingList = BookingList.fromJson(Map<String, dynamic>.from(document.data));
         
          return bookingList;
        }).toList();
      } catch (e) {
        print("Exception $e");
        return [];
      }
    }
    return [];
  }

关于firebase - 如何将数据从Firebase存储到Model类:Flutter ，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/63841540/

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Answer 1

首先，您必须使用fromJson函数创建模型类，该函数将json转换为模型类。我为您准备了类(class)。您也可以从这里https://javiercbk.github.io/json_to_dart/

class BookingList {
  String bookingId;
  String userId;
  String vendorId;
  String mealName;
  String timestamp;
  bool paymentStatus;
  int mealPrice;

  BookingList(
      {this.bookingId,
      this.userId,
      this.vendorId,
      this.mealName,
      this.timestamp,
      this.paymentStatus,
      this.mealPrice});

  BookingList.fromJson(Map<String, dynamic> json) {
    bookingId = json['bookingId'];
    userId = json['userId'];
    vendorId = json['vendorId'];
    mealName = json['mealName'];
    timestamp = json['timestamp'];
    paymentStatus = json['paymentStatus'];
    mealPrice = json['mealPrice'];
  }

  Map<String, dynamic> toJson() {
    final Map<String, dynamic> data = new Map<String, dynamic>();
    data['bookingId'] = this.bookingId;
    data['userId'] = this.userId;
    data['vendorId'] = this.vendorId;
    data['mealName'] = this.mealName;
    data['timestamp'] = this.timestamp;
    data['paymentStatus'] = this.paymentStatus;
    data['mealPrice'] = this.mealPrice;
    return data;
  }
}

然后，您必须解析Firebase中的数据。

Future<List<BookingList>> getAllData() async {
    print("Active Users");
    var val = await fireStore
        .collection("booking")
        .getDocuments();
    var documents = val.documents;
    print("Documents ${documents.length}");
    if (documents.length > 0) {
      try {
        print("Active ${documents.length}");
        return documents.map((document) {
          BookingList bookingList = BookingList.fromJson(Map<String, dynamic>.from(document.data));
         
          return bookingList;
        }).toList();
      } catch (e) {
        print("Exception $e");
        return [];
      }
    }
    return [];
  }