---
title: 'Swift - Loop'
---

while
---

var total = 0, index = 1

while index <= 10 {
    total += index
    index += 1
}

print("1 加到 \(index-1) 的總和為 \(total) ")

**output**
> 1 加到 10 的總和為 55

repeat...while
---

var total = 0, index = 1

repeat{
    total += index
    index += 1
}while index <= 10

print("1 加到 \(index-1) 的總和為 \(total) ")

**output**
> 1 加到 10 的總和為 55

for-in
---

var total = 0

for index in 1...10 {
    total += index
}

print("1 加到 10 的總和為 \(total) ")

**output**
> 1 加到 10 的總和為 55

var string = "Swfit"

//印出字串中的所有字元
for char in string {
    print(char)
}

**output**
> S
w
f
i
t

let end = 3

//不會用到區間值，用“_”代替
for _ in 1...end {
    print("Hello World!")
}

**output**
> Hello World!
Hello World!
Hello World!
###### tags: `Swift`