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iOS Intermediate Swift 2 Extensions and Protocols Extending a Native Type

Posted by Abderrahim Gdah
Abderrahim Gdah
1,326 Points

can someone help me ?

i didn't understand what the task want from me .. add to that i didn't know how to know if the string contain an Int value or Not

types.swift 
extension String {
var add : Int {
if ()


}
}

1 Answer

Amir Gamil
Amir Gamil
5,657 Points
Amir Gamil
Amir Gamil
5,657 Points

The way to find out whether a string can be int is by using the conversion Int() and passing the string as an argument. If it returns nil, then it cannot be converted into a number otherwise it can. Something like this where you can then just add the number

var add: String{ If Int(self) != nil{ //assign the string to an integer constant and return the added expression } else{ return nil } }

Hope this helps!

Abderrahim Gdah
Abderrahim Gdah
1,326 Points

thanks