How do I load a text file line by line into an array with Swift?

Question

How do I load a text file line by line into an array with swift?

Answer 1

This works only until Xcode 6.1 beta 1. In 6.1 beta 2 you must write this:

var err: NSError? = NSError()
let s = String(contentsOfFile: fullPath, encoding: NSUTF8StringEncoding, error: &err)

Where fullPath is a string containing the full path to the file and NSUTF8StringEncoding is a predefined constant for UTF8-Encoding.

You can also use NSMacOSRomanStringEncoding for Mac files or NSISOLatin1StringEncoding for Windows files.

s is an optional String and you can look if reading the file was successful:

if (s != nil)
{
    return (s!) // Return the string as "normal" string, not as optional string
}

Answer 2

Something along the lines of:

func arrayFromContentsOfFileWithName(fileName: String) -> [String]? {
    guard let path = NSBundle.mainBundle().pathForResource(fileName, ofType: "txt") else {
        return nil
    }

    do {
        let content = try String(contentsOfFile:path, encoding: NSUTF8StringEncoding)
        return content.componentsSeparatedByString("\n")
    } catch _ as NSError {
        return nil
    }
}

This approach assumes the file in question is located in your app bundle.

Answer 3

If you are in Swift 2.0, you should use:

let path = NSBundle.mainBundle().pathForResource(fileName, ofType: nil)
if path == nil {
  return nil
}

var fileContents: String? = nil
do {
  fileContents = try String(contentsOfFile: path!, encoding: NSUTF8StringEncoding)
} catch _ as NSError {
  return nil
}