Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

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

swift - Check string for nil & empty

Is there a way to check strings for nil and "" in Swift? In Rails, I can use blank() to check.

I currently have this, but it seems overkill:

    if stringA? != nil {
        if !stringA!.isEmpty {
            ...blah blah
        }
    }
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 Answer

0 votes
by (71.8m points)

If you're dealing with optional Strings, this works:

(string ?? "").isEmpty

The ?? nil coalescing operator returns the left side if it's non-nil, otherwise it returns the right side.

You can also use it like this to return a default value:

(string ?? "").isEmpty ? "Default" : string!

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 OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...