Is Provider.of(context, listen: false) equivalent to context.read()?

问题

// Are these the same?
final model = Provider.of<Model>(context, listen: false); 
final model = context.read<Model>(); 

// Are these the same?
final model = Provider.of<Model>(context);
final model = context.watch<Model>();

Are they the same or aren't they? If they are, then why do I get this error when I use read inside the build() method, while Provider.of() works?

Tried to use context.read<Model> inside either a build method or the update callback of a provider.

回答1:

Well, they aren't the same.

You shouldn't use read inside the build method. Instead stick to the old is gold pattern:

final model = Provider.of<Model>(context, listen: false); 

read is used when you want to use the above pattern in a callback, for instance, when a button is pressed, then we can say they both are performing the same action.

onPressed: () {
  final model = context.read<Model>(); // recommended
  final model = Provider.of<Model>(context, listen: false); // works too
}

回答2:

final model = context.read<Model>();
This returns the Model without listening for any changes.

final model = context.watch<Model>();
This makes the widget listen for changes on the Model.

final model = Provider.of<Model>(context, listen: false);
This works the same as context.read<Model>();

final model = Provider.of<Model>(context);
This works the same as context.watch<Model>();

Recommendations:
Use context.read(), context.watch() instead of Provider.of(). For more insights, refer to this, this & this.

回答3:

Well I don't know about context.read<Model>, but Provider.of<Model>(context, listen: false); is used for example if you want to call a function inside your Model class without listening to any changes. You can avoid rebuilding your app with that approach and still call functions from your Model.

来源：https://stackoverflow.com/questions/62257064/is-provider-ofcontext-listen-false-equivalent-to-context-read