如何将这个复杂的Json转换为Dart对象
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我有这个复杂的（对我来说）json对象，我想将其转换为dart模型，但我总是遇到一个错误或另一个错误。
这是这样的json对象的列表：
"type": "FeatureCollection",
"features": [
"type": "Feature",
"properties":
"name": "Congo",
"pop_est": 4012809,
"gdp_md_est": 15350,
"economy": "6. Developing region",
"income_grp": "4. Lower middle income",
"iso_a2": "CG",
"iso_a3": "COG",
"continent": "Africa",
"latitude": "-4.2634",
"longitude": "15.2832",
"confirmed": 143,
"deaths": 6,
"active": 126,
"recovered": 11
,
"geometry":
"type": "Polygon",
"coordinates": [
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12.995517205465177,
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],
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],
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],
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],
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],
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],
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],
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],
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],
[
17.66355268725468,
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],
[
17.638644646889986,
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],
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17.523716261472856,
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[
16.865306837642123,
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],
[
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],
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15.972803175529151,
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],
[
16.0062895036543,
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],
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],
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],
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],
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],
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]
]
]
,
"type": "Feature",
"properties":
"name": "Angola",
"pop_est": 12799293,
"gdp_md_est": 110300,
"economy": "7. Least developed region",
"income_grp": "3. Upper middle income",
"iso_a2": "AO",
"iso_a3": "AGO",
"continent": "Africa",
"latitude": "-11.2027",
"longitude": "17.8739",
"confirmed": 24,
"deaths": 2,
"active": 16,
"recovered": 6
,
"geometry":
"type": "MultiPolygon",
"coordinates": [
[
[
[
16.326528354567046,
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],
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],
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16.86019087084523,
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],
[
17.08999596524717,
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],
[
17.472970004962292,
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],
[
18.13422163256905,
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],
[
18.464175652752687,
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],
[
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],
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],
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],
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],
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],
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],
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],
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],
[
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],
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],
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],
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],
[
[
[
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],
[
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],
[
11.914963006242116,
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],
[
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12.62075971848455,
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[
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],
[
12.436688266660923,
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]
]
]
]
] //Missing bracket
但是我只需要这部分：
"properties":
"name": "Angola",
"pop_est": 12799293,
"gdp_md_est": 110300,
"economy": "7. Least developed region",
"income_grp": "3. Upper middle income",
"iso_a2": "AO",
"iso_a3": "AGO",
"continent": "Africa",
"latitude": "-11.2027",
"longitude": "17.8739",
"confirmed": 24,
"deaths": 2,
"active": 16,
"recovered": 6
,
我尝试为上面需要的零件创建模型，如下所示：
class AfricaData
Properties properties;
AfricaData(this.properties);
AfricaData.fromJson(Map<String, dynamic> json)
properties = json['properties'] != null
? new Properties.fromJson(json['properties'])
: null;
Map<String, dynamic> toJson()
final Map<String, dynamic> data = new Map<String, dynamic>();
if (this.properties != null)
data['properties'] = this.properties.toJson();
return data;
class Properties
String name;
int popEst;
int gdpMdEst;
String economy;
String incomeGrp;
String isoA2;
String isoA3;
String continent;
String latitude;
String longitude;
int confirmed;
int deaths;
int active;
int recovered;
Properties(
this.name,
this.popEst,
this.gdpMdEst,
this.economy,
this.incomeGrp,
this.isoA2,
this.isoA3,
this.continent,
this.latitude,
this.longitude,
this.confirmed,
this.deaths,
this.active,
this.recovered);
Properties.fromJson(Map<String, dynamic> json)
name = json['name'];
popEst = json['pop_est'];
gdpMdEst = json['gdp_md_est'];
economy = json['economy'];
incomeGrp = json['income_grp'];
isoA2 = json['iso_a2'];
isoA3 = json['iso_a3'];
continent = json['continent'];
latitude = json['latitude'];
longitude = json['longitude'];
confirmed = json['confirmed'];
deaths = json['deaths'];
active = json['active'];
recovered = json['recovered'];
Map<String, dynamic> toJson()
final Map<String, dynamic> data = new Map<String, dynamic>();
data['name'] = this.name;
data['pop_est'] = this.popEst;
data['gdp_md_est'] = this.gdpMdEst;
data['economy'] = this.economy;
data['income_grp'] = this.incomeGrp;
data['iso_a2'] = this.isoA2;
data['iso_a3'] = this.isoA3;
data['continent'] = this.continent;
data['latitude'] = this.latitude;
data['longitude'] = this.longitude;
data['confirmed'] = this.confirmed;
data['deaths'] = this.deaths;
data['active'] = this.active;
data['recovered'] = this.recovered;
return data;
到目前为止，我已经尝试了以下方法：
1）
var data = json.decode(response.body);
var dataModel = (data[1]['features'][0]['properties'] as List).map((f) => AfricaData.fromJson(f)).toList();
2）
Map<String, dynamic> data = json.decode(response.body);
var dataModel = (data['type']['features']['type']['properties'] as List).map((f) => AfricaData.fromJson(f)).toList();
但是我一直得到不同的错误，特别是InternalLinkedHashMap'不是强制类型转换中'List'类型的子类型>]
我有这个复杂的（对我来说）json对象，我想将其转换为dart模型，但我不断遇到一个错误或另一个错误。它是这样的json对象的列表：“ type”：“ FeatureCollection”，...
答案
为了帮助您，您可以使用从json到Dart的转换器
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