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
    }

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。

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)"
    }
}

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)")

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

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。