coursera swift programming

default: 7println"Not a safe place for humans") 8 } 9}Else { Tenprintln"there isn ' t a planet at position \ (positiontofind)") One } A //prints "There isn ' t a planet at position 9This example uses an optional binding (optional binding), which attempts to access a planet through the original value 9. If Let someplanet = Planet.fromraw (9) statement obtains an optional Planet, if optional Planet can be obtained, the someplanet is set to the content of the optional Planet. In this exa

then the loop repeats until the condition is false.　　Conditional statementsIf statementSame as C, no introduction here.Switch statementThe switch statement attempts to match a value to a number of patterns (pattern). The switch statement executes the corresponding code according to the first successful pattern. The If statement is usually replaced with a switch statement when it is possible to have more cases.Switch statements consist of multiple case. To match some of the more specific values,

; "src="/HTTP/ S1.51cto.com/wyfs02/m02/7d/13/wkiom1bfvvoy7isfaailyyxwcke072.jpg "border=" 0 "vspace=" 0 "hspace=" 0 "alt=" Wkiom1bfvvoy7isfaailyyxwcke072.jpg "/>Welcome to follow Dongsheng Sina Weibo@tony_Dongsheng. Learn about the latest technical articles, books, tutorials and information on the public platform of the smart Jie classroom650) this.width=650; "Width=" "height=" "title=" Qrcode_for_gh_ca9759a5ef7f_258.jpg "style=" width:150px;height : 150px; "src=" http://s2.51cto.com/wyfs02/M00/

法习惯和 try? try! 类似.* 数组具体化类型声明为 Any / AnyObject 时,数组内可同时存放多种类型不兼容的实例.Nested Types* 支持类型嵌套定义,这已经是很大的突破了.* 即使在函数内部,也可以定义新的类型.* 可以用.语法,访问嵌套定义的类型.Extensions* extensions 和 categories 的重要区别之一是,前者不需要写名字.* extensions 不允许覆盖已有方法,且不同 extentsion 中的方法签名也不允许重复.* extentsion 扩展的东西,是可以被子类继承的.Protocols* 在swift 的设定中, protocol 也属于 type,可以用于任何 type 适用的场景.* 在类型声明遵循某协议以外的位置,书写符合协议的方法是,用 连接多个协议,如 APBPCP.* protocol 可以在 extension 中定义自己的方法,任意遵循此协议的类型的实例都可以调用此协议自己的方法实现. --> 可以在

Closures are functional self-contained modules that can be passed and used in code. Closures in swift are similar to blocks in C and objective-C, and Lambdas in other programming languages. Closure is acceptable. CaptureAnd store references to any constants and variables in the context. This is the so-called closure and enclose these constants and variables, commonly known as closures.

following results:////// The value returned isIf you create another incrementor, it will have a reference to your own independent runningtotal variable. In the following example, Incrementbysevne captures a new runningtotal variable that has no relation to the variable captured in the Incrementbyten: 7// // The value returned isIf you have a closure assigned to a property of a class instance, and the closure captures the instance by pointing to the instance or its members, you will create a st

Swift is a new development language for Apple in this WWDC conference, and the developer's website has released the introduction, tutorials and manuals for the new language, and if you have an iOS device in hand, search for Swift from its official bookstore via Apple's ibooks app, An ebook version of its Official handbook can be downloaded.Why is Apple launching a new language? Personal humble opinion, now

the current speed. The Automaticcar also provides a custom description method to output the current stop. class Automaticcar:car { var gear = 1 override var speed:double {didset {gear = Int (Speed/10.0 ) + 1 override func description ()-> String { return super.description () + } } When you set the Speed property of the Automaticcar, the Didset Viewer of the property automatically sets the Gear property to select a suitable stop for the new velocity. Specifically, the proper

Unlike other programming languages, Swift does not require you to create separate interfaces and implementation files for your custom classes and structs. All you have to do is define a class or struct in a single file, and the system will automatically generate external interfaces for other code.　　Note: Typically an instance of a class is called an object. However, in