使用fmt包來格式化字串

fmt.Printf()格式字串：

    //整型
    a := 15
    fmt.Printf("a = %b\n", a) //a = 1111
    fmt.Printf("%%\n")        //只輸出一個%

    //字元
    ch := 'a'
    fmt.Printf("ch = %c, %c\n"
 
, ch, 97) //a, a

    //浮點型
    f := 3.14
    fmt.Printf("f = %f, %g\n", f, f) //f = 3.140000, 3.14
    fmt.Printf("f type = %T\n", f)   //f type = float64

    //複數型別
    v := complex(3.2, 12)
    fmt.Printf("v = %f, %g\n", v, v) //v = (3.200000+12.000000i), (3.2+12i)
    fmt.Printf("v type = %T\n", v)   //v type = complex128

    //布林型別
    fmt.Printf("%t, %t\n", true, false) //true, false

    //字串
    str := "hello go"
    fmt.Printf("str = %s\n", str) //str = hello go

型別轉換

Go語言中不允許隱式轉換，所有型別轉換必須顯式宣告，而且轉換隻能發生在兩種相互相容的型別之間。

    var ch byte = 97
    //var a int = ch //err, cannot use ch (type byte) as type int in assignment
    var a int = int(ch)

類型別名

    type bigint int64 //int64型別改名為bigint
    var x bigint = 100

    type (
        myint int    //int改名為myint
        mystr string //string改名為mystr
    )