斯威夫特5.3

let infoDictionaryKey = kCFBundleVersionKey as String
guard let currentVersion = Bundle.main.object(forInfoDictionaryKey: infoDictionaryKey) as? String
else { fatalError("Expected to find a bundle version in the info dictionary") }

EDIT

Swift 4.2更新

let appVersion = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String

EDIT

正如@azdev在Xcode的新版本上指出的那样，你会得到一个编译错误，尝试我以前的解决方案，要解决这个问题，只需编辑它，建议使用一个打开包字典!

let nsObject: AnyObject? = Bundle.main.infoDictionary!["CFBundleShortVersionString"]

最后编辑

使用与Objective-C中相同的逻辑，但有一些小的变化

//First get the nsObject by defining as an optional anyObject
let nsObject: AnyObject? = NSBundle.mainBundle().infoDictionary["CFBundleShortVersionString"]

//Then just cast the object as a String, but be careful, you may want to double check for nil
let version = nsObject as! String

我知道这个问题已经有人回答了，但我个人认为这个问题更清晰一些:

斯威夫特3.0:

 if let version = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String {
    self.labelVersion.text = version
}

斯威夫特< 2.3

if let version = NSBundle.mainBundle().infoDictionary?["CFBundleShortVersionString"] as? String {
    self.labelVersion.text = version
}

这样，if let版本就负责条件处理(在我的例子中设置标签文本)，如果infoDictionary或CFBundleShortVersionString为nil，则可选的展开将导致代码被跳过。

Swift 5更新

这是一个函数，我使用来决定是否显示“应用程序更新”页面或不。它返回版本号，我正在将其转换为Int类型:

if let version: String = Bundle.main.infoDictionary?["CFBundleVersion"] as? String {
        guard let intVersion = Int(version) else { return }
        
        if UserDefaults.standard.integer(forKey: "lastVersion") < intVersion {
            print("need to show popup")
        } else {
            print("Don't need to show popup")
        }
        
        UserDefaults.standard.set(intVersion, forKey: "lastVersion")
    }

如果以前从未使用过，它将返回0，小于当前版本号。若要不向新用户显示这样的屏幕，只需在首次登录后或登录完成时添加构建号。

对于Swift 5.0:

let appVersion = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as! String

斯威夫特5.3

let infoDictionaryKey = kCFBundleVersionKey as String
guard let currentVersion = Bundle.main.object(forInfoDictionaryKey: infoDictionaryKey) as? String
else { fatalError("Expected to find a bundle version in the info dictionary") }