platform/packages/json_god/README.md

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2021-03-07 15:56:09 +00:00
# JSON God v2
[![Pub](https://img.shields.io/pub/v/json_god.svg)](https://pub.dartlang.org/packages/json_god)
[![build status](https://travis-ci.org/thosakwe/json_god.svg)](https://travis-ci.org/thosakwe/json_god)
The ***new and improved*** definitive solution for JSON in Dart.
# Installation
dependencies:
json_god: ^2.0.0-beta
# Usage
It is recommended to import the library under an alias, i.e., `god`.
```dart
import 'package:json_god/json_god.dart' as god;
```
## Serializing JSON
Simply call `god.serialize(x)` to synchronously transform an object into a JSON
string.
```dart
Map map = {"foo": "bar", "numbers": [1, 2, {"three": 4}]};
// Output: {"foo":"bar","numbers":[1,2,{"three":4]"}
String json = god.serialize(map);
print(json);
```
You can easily serialize classes, too. JSON God also supports classes as members.
```dart
class A {
String foo;
A(this.foo);
}
class B {
String hello;
A nested;
B(String hello, String foo) {
this.hello = hello;
this.nested = new A(foo);
}
}
main() {
God god = new God();
print(god.serialize(new B("world", "bar")));
}
// Output: {"hello":"world","nested":{"foo":"bar"}}
```
If a class has a `toJson` method, it will be called instead.
## Deserializing JSON
Deserialization is equally easy, and is provided through `god.deserialize`.
```dart
Map map = god.deserialize('{"hello":"world"}');
int three = god.deserialize("3");
```
### Deserializing to Classes
JSON God lets you deserialize JSON into an instance of any type. Simply pass the
type as the second argument to `god.deserialize`.
If the class has a `fromJson` constructor, it will be called instead.
```dart
class Child {
String foo;
}
class Parent {
String hello;
Child child = new Child();
}
main() {
God god = new God();
Parent parent = god.deserialize('{"hello":"world","child":{"foo":"bar"}}', Parent);
print(parent);
}
```
**Any JSON-deserializable classes must initializable without parameters.
If `new Foo()` would throw an error, then you can't use Foo with JSON.**
This allows for validation of a sort, as only fields you have declared will be
accepted.
```dart
class HasAnInt { int theInt; }
HasAnInt invalid = god.deserialize('["some invalid input"]', HasAnInt);
// Throws an error
```
An exception will be thrown if validation fails.
# Thank you for using JSON God
Thank you for using this library. I hope you like it.
Feel free to follow me on Twitter:
[@thosakwe](http://twitter.com/thosakwe)
Or, check out [my blog](https://thosakwe.com)