iOS:在本地化时为应用程序设置主要语言

import Foundation

func getCurrentLocale() -> String {
    let locale = NSLocale.current
    let languageCode = locale.languageCode
    let countryCode = locale.countryCode
    return languageCode + "_" + countryCode
}

import I18n

let message = NSLocalizedString("MY_KEY", comment: "")

// Localized string for "ADD"
let addString = NSLocalizedString("ADD", comment: "")

let bundle = NSBundle.mainBundle()
let path = bundle.pathForResource("Localizable", ofType: "strings")
let fileManager = FileManager.default
let localizedString = try! String(contentsOfFile: path, encoding: .utf8)

// Localized number
let localizedNumber = NSNumber(value: 10000)

// Localized date
let localizedDate = NSDateFormatter.localizedString(from: Date(), dateStyle: .medium, timeStyle: .medium)

// Localized error message
let errorLocalized = NSLocalizedString("ERROR_MESSAGE", comment: "")

let font = UIFont.preferredFont(forTextStyle: UIFont.TextStyle.body)

let font = UIFont(name: "HiraKakuProN-W6", size: 14)

// Localized string for "ADD" in Japanese
let addString = NSLocalizedString("ADD", comment: "")