1. 将字符串”hello,java教程”转化为”hello,go教程”
    1. package main
    3. import (
    4.     "bytes"
    5.     "fmt"
    6.     "strings"
    7. )
    9. func main() {
    10.     str1 := "hello,java教程"
    11.     source := "java"
    12.     target := "go"
    13.     index := strings.Index(str1, source)
    14.     sourceLen := len(source)
    15.     start := str1[:index]
    16.     end := str1[index+sourceLen:]
    18.     var stringBuilder bytes.Buffer
    19.     stringBuilder.WriteString(start)
    20.     stringBuilder.WriteString(target)
    21.     stringBuilder.WriteString(end)
    22.     fmt.Println(stringBuilder.String())
    23. }
    1. 九九乘法表
    1. package main
    3. import "fmt"
    5. func main() {
    6.     for y := 1; y <= 9; y++ {
    7.         for x := 1; x <= y; x++ {
    8.             fmt.Printf("%d*%d=%d ", x, y, x*y)
    9.         }
    10.         fmt.Println()
    11.     }
    12. }
    1. 匿名函数用作回调函数
    1. package main
    3. import "fmt"
    5. func main() {
    6.     visit([]int{1, 2, 3, 4}, func(v int) {
    7.         fmt.Println(v)
    8.     })
    9. }
    11. func visit(list []int, f func(int)) {
    12.     for _, v := range list {
    13.         f(v)
    14.     }
    15. }
    1. 返回多个匿名函数
    1. package main
    3. import "fmt"
    5. func main() {
    6.     f1, f2 := FGen(1, 2)
    7.     fmt.Println(f1())
    8.     fmt.Println(f2(3))
    9. }
    11. func FGen(x, y int) (func() int, func(int) int) {
    12.     sum := func() int {
    13.         return x + y
    14.     }
    15.     avg := func(z int) int {
    16.         return (x + y) * z
    17.     }
    18.     return sum, avg
    19. }
    1. 闭包例子
    1. package main
    3. import "fmt"
    5. func main() {
    6.     generator1 := playerGen1("yasuo")
    7.     name1, hp1 := generator1()
    8.     name2, hp2 := generator1()
    9.     fmt.Println(name1, hp1)
    10.     fmt.Println(name2, hp2)
    11.     generator2 := playerGen2()
    12.     name3, hp3 := generator2("yasuo")
    13.     fmt.Println(name3, hp3)
    14.     name4, hp4 := generator2("yone")
    15.     fmt.Println(name4, hp4)
    16. }
    18. func playerGen1(name string) func() (string, int) {
    19.     hp := 150
    20.     return func() (string, int) {
    21.         hp++
    22.         return name, hp
    23.     }
    25. }
    27. func playerGen2() func(string) (string, int) {
    28.     hp := 150
    29.     return func(name string) (string, int) {
    30.         hp++
    31.         return name, hp
    32.     }
    33. }
    1. 读文件
    1. package main
    3. import (
    4.     "fmt"
    5.     "io"
    6.     "os"
    7. )
    9. func main() {
    10.     file, err := os.Open("./x.go")
    11.     if err != nil {
    12.         fmt.Println("open file err :", err)
    13.         return
    14.     }
    15.     defer file.Close()
    16.     var buf [128]byte
    17.     var content []byte
    18.     for {
    19.         n, err := file.Read(buf[:])
    20.         if err == io.EOF {
    21.             break
    22.         }
    24.         if err != nil {
    25.             fmt.Println("read file err :", err)
    26.             return
    27.         }
    28.         content = append(content, buf[:n]...)
    29.     }
    30.     fmt.Println(string(content))
    31. }