鉴于Swift一直在发展，我的回答(截至2015年8月):

let version = NSBundle.mainBundle().infoDictionary!["CFBundleVersion"] as! String

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

看过文档后，我认为以下内容更清晰:

let version = 
NSBundle.mainBundle().objectForInfoDictionaryKey("CFBundleShortVersionString") 
as? String

来源: 使用此方法优于其他访问方法，因为它在键可用时返回键的本地化值。

Bundle+Extension.swift (SwiftUI, swift 5, Xcode 11)

我结合了一些答案的想法，并扩展了一点:

一个SwiftUI的例子 如果Info.plist中缺少键，则显示警告三角形表情符号(而不是使应用程序崩溃)

进口的基础

extension Bundle {
    
    public var appVersionShort: String {
        if let result = infoDictionary?["CFBundleShortVersionString"] as? String {
            return result
        } else {
            return "⚠️"
        }
    }
    public var appVersionLong: String {
        if let result = infoDictionary?["CFBundleVersion"] as? String {
            return result
        } else {
            return "⚠️"
        }
    }
    public var appName: String {
        if let result = infoDictionary?["CFBundleName"] as? String {
            return result
        } else {
            return "⚠️"
        }
    }
}

SwiftUI实例使用

VStack {

     Text("Version: \(Bundle.main.appVersionShort!) (\(Bundle.main.appVersionLong!))")
                    .font(.subheadline)
                    .frame(maxWidth: .infinity, maxHeight: .infinity)
}

简单的实用函数返回应用程序版本为Int

func getAppVersion() -> Int {

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

            let appVersionClean = appVersion.replacingOccurrences(of: ".", with: "", options: NSString.CompareOptions.literal, range:nil)

            if let appVersionNum = Int(appVersionClean) {
                return appVersionNum
            }
        }
        return 0
    }

斯威夫特4

func getAppVersion() -> String {
    return "\(Bundle.main.infoDictionary!["CFBundleShortVersionString"] ?? "")"
}

Bundle.main.infoDictionary！[“CFBundleShortVersionString”]

快速旧语法

let appVer: AnyObject? = NSBundle.mainBundle().infoDictionary!["CFBundleShortVersionString"]