Objective-C 简介
探索 Objective-C 的历史和主要特征,了解它在 iOS 生态系统中的作用以及与 C 的关系。
Objective-C 简介 是 CoddyKit 上的免费 Objective-C iOS Development for Legacy & Enterprise Apps 课时。 这是第 1 节课,共 4 节。 你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。 这是 Objective-C iOS Development for Legacy & Enterprise Apps 学习路径的一部分,你的进度在网页和 CoddyKit 应用中同步。 Objective-C iOS Development for Legacy & Enterprise Apps 课程共包含 4 节课。
本课时的部分内容尚未翻译,以英文显示。
Welcome to Objective-C!
Objective-C shaped the early days of iOS and macOS. Swift is newer, but Objective-C still powers a huge base of existing enterprise apps.
Objective-C's Origins
Born in the early 1980s and adopted by NeXT, Objective-C became Apple's primary language for macOS and iOS after the 1997 acquisition.
Objective-C: C's Super-Set
Objective-C is a superset of C: plain C runs inside it, and it layers object-orientation and message passing on top. Powerful, if tricky at first.
Embrace Object-Orientation
Objective-C is object-oriented, but you do not call methods — you send messages to objects with the bracket syntax [object method:arg].
Dynamic Nature of Objective-C
Objective-C has a powerful dynamic runtime: method dispatch is decided at run time, enabling tricks like swizzling and introspection.
Legacy & Enterprise Importance
Why learn it today? Millions of lines of Objective-C still run shipping apps. You need it to maintain legacy code and migrate to Swift.
Hello, CoddyKit!
Your first program. Note the @autoreleasepool for memory and NSLog, which prints like printf but for Objective-C objects.
#import <Foundation/Foundation.h>
int main(int argc, const char * argv[]) {
@autoreleasepool {
NSLog(@"Hello, CoddyKit!");
}
return 0;
}Understanding the Code
Breaking it down: #import pulls in Foundation, main is the entry point, @autoreleasepool manages memory, and NSLog prints.
Behind the Scenes
Behind the scenes Xcode runs four steps to your program: preprocess, compile, link, and run. It handles all of it for you.
Test Your Knowledge!
Based on what we've learned, consider Objective-C's relationship with the C language.
What We've Learned
Recap: Objective-C is a superset of C with OOP, a dynamic runtime, and deep legacy importance — and you ran your first NSLog program.
常见问题解答
「Objective-C 简介」课时是免费的吗?
是的 — 「Objective-C 简介」的完整文本可在网页上免费阅读。要进行交互式练习(内置代码编辑器和全天候 AI 导师)并解锁 Objective-C iOS Development for Legacy & Enterprise Apps 课程的其余内容,请升级到 CoddyKit PRO。 Objective-C iOS Development for Legacy & Enterprise Apps 课程共包含 4 节课。
「Objective-C 简介」这节课中我会学到什么?
探索 Objective-C 的历史和主要特征,了解它在 iOS 生态系统中的作用以及与 C 的关系。 你通过在浏览器中直接运行的动手代码来练习 Objective-C iOS Development for Legacy & Enterprise Apps,全天候 AI 导师会在你学习这节课的过程中回答你的问题。
学习 Objective-C iOS Development for Legacy & Enterprise Apps 需要有经验吗?
无需任何先前经验。CoddyKit 上的 Objective-C iOS Development for Legacy & Enterprise Apps 课程适合初学者到高级学习者,你可以从这里开始或从头开始,按照自己的节奏学习。 这是第 1 节课,共 4 节。
「Objective-C 简介」课时需要多长时间?
大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动,所以你能稳步进步,并在网页和应用中从离开的地方继续。
我能在这节 Objective-C iOS Development for Legacy & Enterprise Apps 课中编写并运行代码吗?
能。每节 Objective-C iOS Development for Legacy & Enterprise Apps 课都包含内置代码编辑器,你可以在浏览器中直接编写并运行真实代码,并获得即时 AI 反馈 — 无需本地设置。