Swift - for-in 循环

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  简述

  for-in 循环遍历项目集合，例如数字范围、数组中的项目或字符串中的字符 -
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  句法

  的语法 for-in Swift 4 编程语言中的循环是 -

  
  for index in var {
     statement(s)
  }
  

  

  Example

  
  var someInts:[Int] = [10, 20, 30]
  for index in someInts {
     print( "Value of index is \(index)")
  }
  

  执行上述代码时，会产生以下结果 -

  
  Value of index is 10
  Value of index is 20
  Value of index is 30