斯威夫特4

//首先通过定义一个可选的AnyObject来获取nsObject

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

//然后将对象转换为String，但要小心，你可能需要再次检查是否为nil

let version = nsObject as! String

现在您可以使用常量来实现这一点，而不必像以前那样使用字符串类型的代码，这使得事情变得更加方便。

var appVersion: String {
    return Bundle.main.infoDictionary![kCFBundleVersionKey as String] 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。

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") }

if let version = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String {
        lblVersion.text = "Version \(version)"

    }

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)
}