Swift 4的更新答案

let language = Bundle.main.preferredLocalizations.first

SWIFT-4

 // To get device default selected language. It will print like short name of zone. For english, en or spain, es.

let language = Bundle.main.preferredLocalizations.first! as NSString
print("device language",language)

选择的答案返回当前设备语言，但不是应用程序中使用的实际语言。如果你没有在应用程序中为用户的首选语言提供本地化，则使用第一个可用的本地化，按用户的首选顺序排序。

要发现在本地化中选择的当前语言，请使用

[[NSBundle mainBundle] preferredLocalizations];

例子:

NSString *language = [[[NSBundle mainBundle] preferredLocalizations] objectAtIndex:0];

迅速:

let language = NSBundle.mainBundle().preferredLocalizations.first as NSString

如果你只想得到语言，这里是我建议的答案:

NSString *langplusreg = [[NSLocale preferredLanguages] objectAtIndex:0];
NSString * langonly = [[langplusreg componentsSeparatedByString:@"-"] 
objectAtIndex:0];

在我的情况下，我只是想Locale语言而不是Locale区域。

输出: 如果你的区域语言是日语，区域区域是日本，那么:

朗加雷格 = 是-JP

朗只 = 和

I actually misread the original question, thought it asked for the "app UI" language (that's what I had googled for), not the "device UI", in which case the best answers would be the ones using preferredLocalizations, but those answers still give you a code, there is one more step to get a nice string to display. So, while the "device UI" language is already answered, if you want to display a nice string for which of the UI languages you support is currently in use, obviously the simplest solution is:

NSLocalizedString(@"currentLanguage", @"")

在你的每一个UI本地化中你都指定了你想要的显示方式。例如，在你的。strings文件的en版本中，你会有:

"currentLanguage"="English";

在你的fr版本的.strings文件中，你会有:

"currentLanguage"="Francais";

等。不要混淆代码等，你可以让你自己的字符串很好地匹配你的UI。

我试图为自己找出正确的解决办法。当我使用Locale.preferredLanguages.first从你的应用程序设置返回首选语言。

如果你想从用户设备设置中了解语言，你应该使用下面的字符串:

斯威夫特3

let currentDeviceLanguage = Locale.current.languageCode
// Will return the optional String

要展开并使用，请看下面这行:

if let currentDeviceLanguage = Locale.current.languageCode {
    print("currentLanguage", currentDeviceLanguage)

    // For example
    if currentDeviceLanguage == "he" {
        UIView.appearance().semanticContentAttribute = .forceRightToLeft
    } else {
        UIView.appearance().semanticContentAttribute = .forceLeftToRight
    }
}