- Dart:Scalable Application Development
- Davy Mitchell Sergey Akopkokhyants Ivo Balbaert
- 212字
- 2021-07-09 18:56:18
Accessing private fields
In Dart, as discussed when we covered packages, the privacy is at the library level, but it is still possible to have private fields in a class even though Dart does not have the keywords public, protected, and private. A simple return of a private field's value can be performed with a one-line function:
String getFirstName() => _name;
To retrieve this value, a function call is required, for example, Person.getFirstName();
however, it may be preferable to have a property syntax such as Person.firstName
. Having private fields and retaining the property syntax in this manner is possible using the get
and set
keywords.
Using true getters and setters
The syntax of Dart also supports get
and set
via keywords:
int get score => score + bonus; set score(int increase) => score += increase * level;
Using either get
/set
or simple fields is down to preference. It is perfectly possible to start with simple fields and scale up to getters and setters if more validation or processing is required.
The advantage of the get
and set
keywords in a library is that the intended interface for consumers of the package is very clear. Further, it clarifies which methods may change the state of the object and which merely report current values.
- 解構產品經理:互聯網產品策劃入門寶典
- 劍指Offer(專項突破版):數據結構與算法名企面試題精講
- Vue.js快速入門與深入實戰
- TestNG Beginner's Guide
- C語言程序設計案例式教程
- GameMaker Programming By Example
- Python完全自學教程
- Windows Server 2016 Automation with PowerShell Cookbook(Second Edition)
- Getting Started with Eclipse Juno
- C++ Fundamentals
- Windows Phone 8 Game Development
- 嵌入式Linux C語言程序設計基礎教程
- 多媒體技術及應用
- Application Development with Swift
- Visual C++程序設計與項目實踐