Flutter：如何解码多个 json 数据数组？

问题描述

这是我拥有的 json 数据：

{ "data": [ { "id": "23","type": "product","attributes": { "slug": "","name": "",},"relationships": {} },{ "id": "25",{ "id": "30",{ "id": "31","relationships": {} } ],"included": [ { "id": "106","type": "image","attributes": { "viewable_type": "","viewable_id": 48,"mobile_image_styles": { "mini": { "url": "","size": "48x48>","width": 48,"height": 48 },"small": { "url": "","size": "100x100>","width": 100,"height": 100 } } } } ] }

我的问题是：我如何编写模型并解码这个 json 数据？

This is sameple json

*** 编辑： 这就是我只解码 ['data'] 的方式，但现在它已经“包含”了，所以如何解码它？==> var res = await productApi.getResult(pageNumber,status); var responseJson = json.decode(res); var list = (responseJson['data'] as List) .map((p) => ProductModel2.fromJson(p)) .toList();

解决方法

使用 JSON 模型的一个很棒的工具是 quicktype

您可以粘贴您的数据，它会为您创建一个解析器。
选择 Dart 作为输出语言。

此外，您的数据似乎存在错误，属性名称后有额外的昏迷。
我使用这个示例来使用生成器：

{ 
"data": [ 
    { 
        "id": "23","type": "product","attributes": { 
            "slug": "","name": ""
        },"relationships": {} 
    } 
],"included": [ 
    { 
        "id": "106","type": "image","attributes": {
            "viewable_type": "","viewable_id": "48","mobile_image_styles": {
                "mini": { 
                    "url": "","size": "48x48>","width": 48,"height": 48 
                },"small": { 
                    "url": "","size": "100x100>","width": 100,"height": 100
                } 
            } 
        } 
    } 
  ]
}

,

您可以根据需要使用 this website 生成模型类。这是我从那里得到的。

// To parse this JSON data,do
//
//     final welcome = welcomeFromMap(jsonString);

import 'dart:convert';

Welcome welcomeFromMap(String str) => Welcome.fromMap(json.decode(str));

String welcomeToMap(Welcome data) => json.encode(data.toMap());

class Welcome {
    Welcome({
        this.data,this.included,});

    List<Datum> data;
    List<Included> included;

    factory Welcome.fromMap(Map<String,dynamic> json) => Welcome(
        data: List<Datum>.from(json["data"].map((x) => Datum.fromMap(x))),included: List<Included>.from(json["included"].map((x) => Included.fromMap(x))),);

    Map<String,dynamic> toMap() => {
        "data": List<dynamic>.from(data.map((x) => x.toMap())),"included": List<dynamic>.from(included.map((x) => x.toMap())),};
}

class Datum {
    Datum({
        this.id,this.type,this.attributes,this.relationships,});

    String id;
    String type;
    DatumAttributes attributes;
    Relationships relationships;

    factory Datum.fromMap(Map<String,dynamic> json) => Datum(
        id: json["id"],type: json["type"],attributes: DatumAttributes.fromMap(json["attributes"]),relationships: Relationships.fromMap(json["relationships"]),dynamic> toMap() => {
        "id": id,"type": type,"attributes": attributes.toMap(),"relationships": relationships.toMap(),};
}

class DatumAttributes {
    DatumAttributes({
        this.slug,this.name,});

    String slug;
    String name;

    factory DatumAttributes.fromMap(Map<String,dynamic> json) => DatumAttributes(
        slug: json["slug"],name: json["name"],dynamic> toMap() => {
        "slug": slug,"name": name,};
}

class Relationships {
    Relationships();

    factory Relationships.fromMap(Map<String,dynamic> json) => Relationships(
    );

    Map<String,dynamic> toMap() => {
    };
}

class Included {
    Included({
        this.id,});

    String id;
    String type;
    IncludedAttributes attributes;

    factory Included.fromMap(Map<String,dynamic> json) => Included(
        id: json["id"],attributes: IncludedAttributes.fromMap(json["attributes"]),};
}

class IncludedAttributes {
    IncludedAttributes({
        this.viewableType,this.viewableId,this.mobileImageStyles,});

    String viewableType;
    int viewableId;
    MobileImageStyles mobileImageStyles;

    factory IncludedAttributes.fromMap(Map<String,dynamic> json) => IncludedAttributes(
        viewableType: json["viewable_type"],viewableId: json["viewable_id"],mobileImageStyles: MobileImageStyles.fromMap(json["mobile_image_styles"]),dynamic> toMap() => {
        "viewable_type": viewableType,"viewable_id": viewableId,"mobile_image_styles": mobileImageStyles.toMap(),};
}

class MobileImageStyles {
    MobileImageStyles({
        this.mini,this.small,});

    Mini mini;
    Mini small;

    factory MobileImageStyles.fromMap(Map<String,dynamic> json) => MobileImageStyles(
        mini: Mini.fromMap(json["mini"]),small: Mini.fromMap(json["small"]),dynamic> toMap() => {
        "mini": mini.toMap(),"small": small.toMap(),};
}

class Mini {
    Mini({
        this.url,this.size,this.width,this.height,});

    String url;
    String size;
    int width;
    int height;

    factory Mini.fromMap(Map<String,dynamic> json) => Mini(
        url: json["url"],size: json["size"],width: json["width"],height: json["height"],dynamic> toMap() => {
        "url": url,"size": size,"width": width,"height": height,};
}

,

一种简单的方法是使用工厂构造函数。

factory Class.fromJson(Map<String,dynamic> json) {
    return Class(
      variableName: json['variableName'],);

将您的 json 文件传递​​给类工厂构造函数，如下所示：

json = someJsonFile;
Class obj = Class.fromJson(json['variableName']);