Using flutter docs am trying to learn json deserialization. But I am getting the following error "The argument type 'Map<String, String>' can't be assigned to the parameter type 'String'"
heres the code
import 'dart:convert';
User userFromJson(String str) => User.fromJson(json.decode(str));
void main() {
var jsonString = {
"name": "Martin Perumala",
"email": "[email protected]"
};
User user = User.fromJson(jsonDecode(jsonString) as Map<String,dynamic>);
}
class User {
User({
required this.name,
required this.email,
});
String name;
String email;
factory User.fromJson(Map<String, dynamic> json) => User(
name: json["name"],
email: json["email"],
);
}
CodePudding user response:
It looks like you are trying to parse a JSON string and are encountering an error. To parse a JSON string in Flutter, you can use the json.decode()
function from the dart:convert
library. This function takes a string as an input and returns a dynamic
object that represents the JSON structure.
Here's an example of how you can use json.decode()
to parse a JSON string:
import 'dart:convert';
String jsonString = '{"name": "John Smith", "email": "[email protected]"}';
dynamic json = json.decode(jsonString);
print(json['name']); // Output: "John Smith"
print(json['email']); // Output: "[email protected]"
If you are getting the error "The argument type 'Map<String, String>' can't be assigned to the parameter type 'String'," it means that you are trying to pass a Map
object as an argument to the json.decode()
function, but this function expects a string. Make sure that you are passing a string to the json.decode()
function, and not a Map
or any other data type.