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

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

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

针对Swift 4.0

let version = Bundle.main.infoDictionary!["CFBundleShortVersionString"]!
let build = Bundle.main.infoDictionary!["CFBundleVersion"]!

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") }

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。