Learn Golang in Days - Day 11

Learn Golang in Days - Day 11

要点

---

• Range
• Go语言中range关键字用于for循环中迭代数组array,slice,channel or map 的元素。在数组和切片中它返回元素的索引和索引对应的值，在集合中返回key-value的key值。
• range 可以遍历数组，切片
• range 可以遍历字符串
• range 可以遍历map

实例

---

package main

import "fmt"


func main() {
    // ---------------- 定义切片 ----------------
    //定义slice
    nums := []int {1,2,3}
    sum := 0

    for _,num := range nums {
        fmt.Printf("%d,", num)
        sum += num
    }

    fmt.Printf("\nsum= %d\n",sum)
    fmt.Println()

    for i,num := range nums {
        fmt.Printf("nums[%d]=%d\n",i, num)
        sum += num
    }


    // ------------------ Map -------------------
    kvs := map[string]string{"a":"apple","b":"banana"}
    for k,v := range kvs {
        fmt.Printf("%s -> %s\n", k,v)   
    }

    //----------------- String ------------------
    s := "This is a tiger"
    for i,c := range s {
        fmt.Printf("[%d]=%c\n",i,c) 
    }
}