Swift - for-in 循环

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for -in循环迭代项目集合，例如数字范围、数组中的项目或字符串中的字符 -

句法

Swift 4 编程语言中for-in循环的语法是 -

for index in var {
   statement(s)
}

例子

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