以下是Swift 3.2的更新版本:

extension UIApplication
{
    static var appVersion:String
    {
        if let appVersion = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString")
        {
            return "\(appVersion)"
        }
        return ""
    }

    static var buildNumber:String
    {
        if let buildNum = Bundle.main.object(forInfoDictionaryKey: kCFBundleVersionKey as String)
        {
            return "\(buildNum)"
        }
        return ""
    }

    static var versionString:String
    {
        return "\(appVersion).\(buildNumber)"
    }
}

对于任何感兴趣的人，在github上有一个漂亮而整洁的库叫做SwifterSwift，它也有完整的swift版本文档(参见swifterswift.com)。

使用这个库，读取应用版本和构建号就像这样简单:

import SwifterSwift

let buildNumber = SwifterSwift.appBuild
let version = SwifterSwift.appVersion

Swift 5作为UIApplication扩展

extension UIApplication {
    static var release: String {
        return Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as! String? ?? "x.x"
    }
    static var build: String {
        return Bundle.main.object(forInfoDictionaryKey: "CFBundleVersion") as! String? ?? "x"
    }
    static var version: String {
        return "\(release).\(build)"
    }
}

使用示例:

print("release: \(UIApplication.release)")
print("build: \(UIApplication.build)")
print("version: \(UIApplication.version)")

以下是Swift 3.2的更新版本:

extension UIApplication
{
    static var appVersion:String
    {
        if let appVersion = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString")
        {
            return "\(appVersion)"
        }
        return ""
    }

    static var buildNumber:String
    {
        if let buildNum = Bundle.main.object(forInfoDictionaryKey: kCFBundleVersionKey as String)
        {
            return "\(buildNum)"
        }
        return ""
    }

    static var versionString:String
    {
        return "\(appVersion).\(buildNumber)"
    }
}

Xcode 9.4.1 Swift 4.1

注意，使用localizedInfoDictionary来获取包显示名称的正确语言版本。

var displayName: String?
var version: String?
var build: String?

override func viewDidLoad() {
    super.viewDidLoad()

    // Get display name, version and build

    if let displayName = Bundle.main.localizedInfoDictionary?["CFBundleDisplayName"] as? String {
        self.displayName = displayName
    }
    if let version = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String {
        self.version = version
    }
    if let build = Bundle.main.infoDictionary?["CFBundleVersion"] as? String {
        self.build = build
    }
}

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