Swift playground - Instance member cannot be used on type custom class

Question

I'm trying to implement the following code in an playground:

class File {
    class func open(path: String, encoding: NSStringEncoding = NSUTF8StringEncoding) -> String? {
        if NSFileManager().fileExistsAtPath(path) {
            do {
                return try String(contentsOfFile: path, encoding: encoding)
            } catch let error as NSError {
                print(error.code)
                return nil
            }
        }
        return  nil
}

But when I try to access the class:

let read = File()
let content = read.open("ba")

I get this error: "Instance member "read" cannot be used on type custom type "File" "

Any of you knows why of this error or how can I fix it?

I would really appreciate your help.

http://stackoverflow.com/a/26540934/2303865 the answer it is right below the original code — Leo Dabus, May 10 '16 at 22:12
BTW this won't work with playground anymore. you need to test it with a real project — Leo Dabus, May 10 '16 at 22:13

score 2 · Answer 1 · answered May 10 '16 at 21:51

2

You've defined a static method so its accessible like

let content = File.open("ba")

answered May 10 '16 at 21:51

SirH

535
2
7

What is the difference between static method and non- static method? – user2924482 May 10 '16 at 21:54
Methods and variables that are not declared as static are known as instance methods and instance variables. To refer to instance methods and variables, you must instantiate the class first means you should create an object of that class first.For static you don't need to instantiate the class u can access the methods and variables with the class name using period sign which is in (.) – SirH May 10 '16 at 21:57
Why should use over the other? – user2924482 May 11 '16 at 17:11

Swift playground - Instance member cannot be used on type custom class

1 Answers1