Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
818 views
in Technique[技术] by (71.8m points)

swift - Is there a difference between "is" and isKindOfClass()?

Swift provides the is keyword (and as?) to check whether an object can be downcast successfully:

if foo is MyClass {
    // ...
}

But NSObjectProtocol also provides the original func isKindOfClass(aClass: AnyClass!) -> Bool:

if something.isKindOfClass(MyClass) {
    // ...
}

For classes conforming to NSObjectProtocol, is this really much different?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Yes there is a difference: is works with any class in Swift, whereas isKindOfClass() works only with those classes that are subclasses of NSObject or otherwise implement NSObjectProtocol.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...