How to write Application Logs to File and get them

Question

I´m taking baby steps in iOS development and searching for a method to use logging in iOS.

I found these docs about logging with swift 3 : https://developer.apple.co

Answer 1

Swift 3.0 version

Create a new swift file "TextLog.swift" in your project

import Foundation

struct TextLog: TextOutputStream {

    /// Appends the given string to the stream.
    mutating func write(_ string: String) {
        let paths = FileManager.default.urls(for: .documentDirectory, in: .allDomainsMask)
        let documentDirectoryPath = paths.first!
        let log = documentDirectoryPath.appendingPathComponent("log.txt")

        do {
            let handle = try FileHandle(forWritingTo: log)
            handle.seekToEndOfFile()
            handle.write(string.data(using: .utf8)!)
            handle.closeFile()
        } catch {
            print(error.localizedDescription)
            do {
                try string.data(using: .utf8)?.write(to: log)
            } catch {
                print(error.localizedDescription)
            }
        }

    }

}

Initialize the logger at bottom in the AppDelegate.swift file

var textLog = TextLog()

Use it anywhere in the application like below

textLog.write("hello")