CH 3 Interoperabilty with NSString

Mitchb · April 4th, 2015, 12:56 AM

I could not get this code to work. Xcode reports containsString unknown selector.

Code:

var str1 = "This is a Swift string"
println((str1 as NSString).containsString("Swift")) ---true---

You need to be running OS 10.10 before this will work. I'm on 10.9.

Mitch

leonwang777 · June 24th, 2015, 07:04 AM

In chap 3, another error codes for character type conversion to NSString.

var bouquet = "\u{1F490}" // Character

println((bouquet as NSString).length) //Err: Character can't be converted to NSString

println(bouquet)
println("\(bouquet)") // String
println(String(bouquet)) // Character to String
println(count("\(bouquet)")) //---1---
println(count(String(bouquet))) //---1---

From above, you have to convert a Chacater to be a String by String() typecast, then to NSString. It will get error by "as NSString" directly.

println((NSString(string:String(bouquet)))) // Convert a character to a NSString
println((NSString(string:String(bouquet))).length) // ---2---

Leon