Go中格式化輸出

// code_002_basedata project main.go
package main

import (
    "fmt"
)

type Power struct {
    age  int
    high int
    name string
}

func main() {
    var str string
    str = "abc"
    ch := str[0]

    fmt.Printf("str= %s, len= %d \n", str, len(str))
    fmt.Printf("str[0]= %c, ch = %c\n", str[0], ch)

    str2 := `hello
    mike \n \r測試
    `
    fmt.Println("str2=", str2)

    var v1 complex64
    v1 = 3.2 + 12i
    v2 := 3.2 + 12i
    v3 := complex(3.2, 12)
    fmt.Println(v1, v2, v3)
    fmt.Println(real(v1), imag(v1))

    fmt.Println("============")

    var i Power = Power{18, 178, "tom"}
    fmt.Printf("type:%T\n", i)
    fmt.Printf("value:%v\n", i)
    fmt.Printf("value:%+v\n", i)
    fmt.Printf("value:%#v\n", i)
    /*
    ============
    type:main.Power
    value:{18 178 tom}
    value:{age:18 high:178 name:tom}
    value:main.Power{age:18, high:178, name:"tom"}
    */

    fmt.Println("=====intervface=======")
    var interstr interface{} = i
    fmt.Printf("%v\n", interstr)
    fmt.Println(interstr)

    /*
    =====intervface=======
{18 178 tom}
{18 178 tom}
    */
}

//常用的格式化字符：%s, %d, %c, %T, %v, %p