flutter json to class
To convert JSON to a Dart class in Flutter, you can follow these steps:
Define your JSON structure: Start by having a clear understanding of the JSON structure you want to convert. Identify the different fields and their types.
Create a new Dart class: In your Flutter project, create a new Dart file where you'll define the class that represents the JSON structure.
Add the necessary imports: Import the
dart:convert
package to use thejsonDecode
function, which converts a JSON string into a Dart object.Define the class: Inside the Dart file, create a class with the same name as the JSON object. Define the class properties that match the JSON fields.
Implement the factory constructor: Add a factory constructor that takes a
Map<String, dynamic>
as a parameter. Inside the constructor, assign the values of the JSON fields to the class properties.Convert JSON to class instance: To convert the JSON to an instance of the class, use the
jsonDecode
function to parse the JSON string into aMap<String, dynamic>
. Then, pass the map to the factory constructor.
Here's an example of how the code could look:
import 'dart:convert';
class MyData {
final String name;
final int age;
MyData({required this.name, required this.age});
factory MyData.fromJson(Map<String, dynamic> json) {
return MyData(
name: json['name'],
age: json['age'],
);
}
}
void main() {
String jsonString = '{"name": "John Doe", "age": 30}';
Map<String, dynamic> jsonMap = jsonDecode(jsonString);
MyData myData = MyData.fromJson(jsonMap);
print(myData.name);
print(myData.age);
}
In this example, the MyData
class represents a JSON object with name
and age
fields. The fromJson
factory constructor takes a JSON map and assigns the values to the class properties. Finally, we decode the JSON string, create an instance of the MyData
class, and print the values.
You can adapt this code to match your specific JSON structure and class requirements.