extension UIApplication {

    static var appVersion: String {
        if let appVersion = NSBundle.mainBundle().objectForInfoDictionaryKey("CFBundleShortVersionString") {
            return "\(appVersion)"
        } else {
            return ""
        }
    }

    static var build: String {
        if let buildVersion = NSBundle.mainBundle().objectForInfoDictionaryKey(kCFBundleVersionKey as String) {
            return "\(buildVersion)"
        } else {
            return ""
        }
    }

    static var versionBuild: String {
        let version = UIApplication.appVersion
        let build = UIApplication.build

        var versionAndBuild = "v\(version)"

        if version != build {
            versionAndBuild = "v\(version)(\(build))"
        }

        return versionAndBuild
    }

}

注意: 你应该在这里使用if，以防应用程序版本或构建没有设置，这将导致崩溃，如果你尝试使用!打开。

针对Swift 2.0

//First get the nsObject by defining as an optional anyObject

let nsObject: AnyObject? = NSBundle.mainBundle().infoDictionary!["CFBundleShortVersionString"]
let version = nsObject as! String

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

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"]

对于Swift 1.2，它是:

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

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)"
    }
}