来自实例的字符串:

String(describing: self)

类型中的字符串:

String(describing: YourType.self)

例子:

struct Foo {

    // Instance Level
    var typeName: String {
        return String(describing: Foo.self)
    }

    // Instance Level - Alternative Way
    var otherTypeName: String {
        let thisType = type(of: self)
        return String(describing: thisType)
    }

    // Type Level
    static var typeName: String {
        return String(describing: self)
    }

}

Foo().typeName       // = "Foo"
Foo().otherTypeName  // = "Foo"
Foo.typeName         // = "Foo"

用类、结构和enum测试。

斯威夫特5

下面是将typeName作为变量获取的扩展(使用值类型或引用类型)。

protocol NameDescribable {
    var typeName: String { get }
    static var typeName: String { get }
}

extension NameDescribable {
    var typeName: String {
        return String(describing: type(of: self))
    }

    static var typeName: String {
        return String(describing: self)
    }
}

使用方法:

// Extend with class/struct/enum...
extension NSObject: NameDescribable {}
extension Array: NameDescribable {}
extension UIBarStyle: NameDescribable { }

print(UITabBarController().typeName)
print(UINavigationController.typeName)
print([Int]().typeName)
print(UIBarStyle.typeName)

// Out put:
UITabBarController
UINavigationController
Array<Int>
UIBarStyle

这个解决方案适用于所有的类

Swift 5解决方案:

extension NSObject {
  var className: String {
    return String(describing: type(of: self))
  }

  class var className: String {
    return String(describing: self)
  }
}

用法:

class TextFieldCell: UITableVIewCell {
}

class LoginViewController: UIViewController {
  let cellClassName = TextFieldCell.className
}

斯威夫特3.0: 你可以创建一个像这样的扩展..它返回的是类名，而不是项目名

extension NSObject {
    var className: String {
        return NSStringFromClass(self as! AnyClass).components(separatedBy: ".").last ?? ""
    }

    public class var className: String {
        return NSStringFromClass(self).components(separatedBy: ".").last ?? ""
    }
}

在Swift 4.1和现在的Swift 4.2中:

import Foundation

class SomeClass {
    class InnerClass {
        let foo: Int

        init(foo: Int) {
            self.foo = foo
        }
    }

    let foo: Int

    init(foo: Int) {
        self.foo = foo
    }
}

class AnotherClass : NSObject {
    let foo: Int

    init(foo: Int) {
        self.foo = foo
        super.init()
    }
}

struct SomeStruct {
    let bar: Int

    init(bar: Int) {
        self.bar = bar
    }
}

let c = SomeClass(foo: 42)
let s = SomeStruct(bar: 1337)
let i = SomeClass.InnerClass(foo: 2018)
let a = AnotherClass(foo: 1<<8)

如果你周围没有实例:

String(describing: SomeClass.self) // Result: SomeClass
String(describing: SomeStruct.self) // Result: SomeStruct
String(describing: SomeClass.InnerClass.self) // Result: InnerClass
String(describing: AnotherClass.self) // Result: AnotherClass

如果你有一个实例:

String(describing: type(of: c)) // Result: SomeClass
String(describing: type(of: s)) // Result: SomeStruct
String(describing: type(of: i)) // Result: InnerClass
String(describing: type(of: a)) // Result: AnotherClass

斯威夫特5:

方式1:

print("Class: \(String(describing: self)), Function: \(#function), line: \(#line)")

输出:

Class: <Test.ViewController: 0x7ffaabc0a3d0>, Function: viewDidLoad(), line: 15

方式2:

print("Class: \(String(describing: type(of: self))), Function: \(#function), line: \(#line)")

输出:

Class: ViewController, Function: viewDidLoad(), line: 16