Swift for-in Loop
The Swift for-in loop is used to iterate over all elements in a collection, such as numeric ranges, elements in an array, and characters in a string.
Syntax
The syntax format of the Swift for-in loop is as follows:
for index in var {
循环体
}
Flowchart:
Example 1
import Cocoa
for index in 1...5 {
print("\(index) 乘于 5 为:\(index * 5)")
}
The element iterated in the example is a numeric range from 1 to 5 represented by the closed range operator (...). i
The output of the above program execution is:
1 乘于 5 为:5 2 乘于 5 为:10 3 乘于 5 为:15 4 乘于 5 为:20 5 乘于 5 为:25
Example 2
import Cocoa
var someInts:[Int] = [10, 20, 30]
for index in someInts {
print( "index 的值为 \(index)")
}
The output of the above program execution is:
index 的值为 10 index 的值为 20 index 的值为 30Other Extensions
Swift Loops