Swift 4版本

如果您想为NotificationCenter创建一个名称:

extension Notification.Name {
    static let updateDataList1 = Notification.Name("updateDataList1")
}

订阅通知:

NotificationCenter.default.addObserver(self, selector: #selector(youFunction), name: .updateDataList1, object: nil)

发送通知:

NotificationCenter.default.post(name: .updateDataList1, object: nil)

如果你只是想要一个有变量的类:

class Keys {
    static let key1 = "YOU_KEY"
    static let key2 = "YOU_KEY"
}

Or:

struct Keys {
    static let key1 = "YOU_KEY"
    static let key2 = "YOU_KEY"
}

正如其他人所提到的，在类之外声明的任何东西都是全局的。

你也可以创建单例对象:

class TestClass {
    static let sharedInstance = TestClass()
    // Anything else goes here
    var number = 0
}

当你想要使用这个类中的一些东西时，你可以这样写:

TestClass.sharedInstance.number = 1

如果您现在从项目的任何地方写入println(TestClass.sharedInstance.number)，您将向日志中输出1。这适用于所有类型的对象。

tl;dr:任何时候你想让一个类中的所有东西都是全局的，在类中添加静态let sharedInstance = YourClassName()，并用前缀YourClassName.sharedInstance来处理类的所有值

我来晚会晚了一点。

不管这里是我如何管理常量文件，以便它对开发人员更有意义，而写代码在swift。

网址:

//URLConstants.swift

  struct APPURL {

    private struct Domains {
        static let Dev = "http://test-dev.cloudapp.net"
        static let UAT = "http://test-UAT.com"
        static let Local = "192.145.1.1"
        static let QA = "testAddress.qa.com"
    }

    private  struct Routes {
        static let Api = "/api/mobile"
    }

    private  static let Domain = Domains.Dev
    private  static let Route = Routes.Api
    private  static let BaseURL = Domain + Route

    static var FacebookLogin: String {
        return BaseURL  + "/auth/facebook"
    }
}

CUSTOMFONTS:

//FontsConstants.swift
struct FontNames {

    static let LatoName = "Lato"
    struct Lato {
        static let LatoBold = "Lato-Bold"
        static let LatoMedium = "Lato-Medium"
        static let LatoRegular = "Lato-Regular"
        static let LatoExtraBold = "Lato-ExtraBold"
    }
}

应用程序中使用的所有键

//KeyConstants.swift
    struct Key {

        static let DeviceType = "iOS"
        struct Beacon{
            static let ONEXUUID = "xxxx-xxxx-xxxx-xxxx"
        }

        struct UserDefaults {
            static let k_App_Running_FirstTime = "userRunningAppFirstTime"
        }

        struct Headers {
            static let Authorization = "Authorization"
            static let ContentType = "Content-Type"
        }
        struct Google{
            static let placesKey = "some key here"//for photos
            static let serverKey = "some key here"
        }

        struct ErrorMessage{
            static let listNotFound = "ERROR_LIST_NOT_FOUND"
            static let validationError = "ERROR_VALIDATION"
        }
    }

颜色常数:

//ColorConstants.swift
struct AppColor {

    private struct Alphas {
        static let Opaque = CGFloat(1)
        static let SemiOpaque = CGFloat(0.8)
        static let SemiTransparent = CGFloat(0.5)
        static let Transparent = CGFloat(0.3)
    }

    static let appPrimaryColor =  UIColor.white.withAlphaComponent(Alphas.SemiOpaque)
    static let appSecondaryColor =  UIColor.blue.withAlphaComponent(Alphas.Opaque)

    struct TextColors {
        static let Error = AppColor.appSecondaryColor
        static let Success = UIColor(red: 0.1303, green: 0.9915, blue: 0.0233, alpha: Alphas.Opaque) 
    }

    struct TabBarColors{
        static let Selected = UIColor.white
        static let NotSelected = UIColor.black
    }

    struct OverlayColor {
        static let SemiTransparentBlack = UIColor.black.withAlphaComponent(Alphas.Transparent)
        static let SemiOpaque = UIColor.black.withAlphaComponent(Alphas.SemiOpaque)
        static let demoOverlay = UIColor.black.withAlphaComponent(0.6)
    }
}

在Xcode项目中，你可以将这些文件打包到一个名为Constants的公共组中。

更多信息请观看这个视频

对于通知，你可以使用扩展，像这样:

extension Notification.Name {
    static let testNotification = "kTestNotification"
}

然后像NotificationCenter.default.post那样使用它(名称:.testNotification，对象:nil)

Constant.swift

import Foundation

let kBaseURL = NSURL(string: "http://www.example.com/")

ViewController.swift

var manager = AFHTTPRequestOperationManager(baseURL: kBaseURL)

为了在我的应用程序中有全局常量，这是我在一个单独的Swift文件中所做的:

import Foundation

struct Config {
    static let baseURL = "https://api.com"

    static APIKeys {
        static let token = "token"
        static let user = "user"
    }

    struct Notifications {
        static let awareUser = "aware_user"
    }
}

它很容易使用，并且可以像这样调用任何地方:

print(Config.Notifications.awareUser)