#warning：C风格的for语句已弃用，并将在以后的Swift版本中删除

删除for init; comparison; increment {}并删除++和--轻松。并使用Swift的漂亮for-in循环

   // WARNING: C-style for statement is deprecated and will be removed in a future version of Swift
   for var i = 1; i <= 10; i += 1 {
      print("I'm number \(i)")
   }

Swift 2.2：

   // new swift style works well
   for i in 1...10 {
      print("I'm number \(i)")
   }  

递减指数

  for index in 10.stride(to: 0, by: -1) {
      print(index)
  }

或者你可以使用reverse()像

  for index in (0 ..< 10).reverse() { ... }

浮球型 (there is no need to define any types to index)

 for index in 0.stride(to: 0.6, by: 0.1) {
     print(index)  //0.0 ,0.1, 0.2,0.3,0.4,0.5
 }  

Swift 3.0：

从开始Swift3.0，stride(to:by:)Strideable上的方法已替换为自由函数，stride(from:to:by:)

for i in stride(from: 0, to: 10, by: 1){
    print(i)
}

对于中的递减索引Swift 3.0，您可以使用reversed()

for i in (0 ..< 5).reversed() {
    print(i) // 4,3,2,1,0
}

其他则for each和stride()，则可以使用While Loops

var i = 0
while i < 10 {
    i += 1
    print(i)
}

Repeat-While Loop:

var a = 0
repeat {
   a += 1
   print(a)
} while a < 10

在《 Swift编程语言指南》中查看控制流