Golang的range

Golang range实例

rangegolangC++rangerange

1.1 range基础语法

rangegolang

package main
import "fmt"

func main() {
    x := []string{"a", "b", "c"}
    for v := range x {
        fmt.Println(v) 		//prints 0, 1, 2
    }
    for _, v := range x {
        fmt.Println(v) 		//prints a, b, c
    }
}

rangeindexvalue_ ，v = range x_range

1.2 range原理

range

package main
import "fmt"
type student struct {
	Name string
	Age int
}
func main() {
	m := make(map[string]*student)
	stus := []student{
		{Name: "zhou", Age: 24},
		{Name: "li", Age: 23},
		{Name: "wang", Age: 22},
	}
	for _, stu := range stus {
		m[stu.Name] = &stu
	}
	for k, v := range m {
		fmt.Println(k, "=>", v.Name)
	}
}
//输出情况如下，因为遍历map，index为键，value为map中对应的值，每次遍历是无序的
/*
li => wang
wang => wang
zhou => wang
*/

map

然后我们尝试以下边的代码做输出

fmt.Println(m)
//此时输出内容如下
//map[zhou:0xc000046400 li:0xc000046400 wang:0xc000046400]

map[string]*student*studentrangerange

修改版：

	for k, stu := range stus {
		fmt.Println(stu.Name, "=>", &stu)
		m[stus[k].Name] = &stus[k]
	}
    for k,v:=range m{
        println(k,"=>",v.Name)
    }

或者

	for i:=0;i<len(stus);i++  {
        m[stus[i].Name] = &stus[i]
    }
    for k,v:=range m{
        println(k,"=>",v.Name)
    }

range

// setReqBodyLog 请求的body数据落日志
func setReqBodyLog(ctx context.Context, req *http.Request) {
	formMap := map[string]string{}
	for k, v := range req.PostForm {
		for _, formV := range v {
			if formMap[k] == "" {
				formMap[k] = desensitization.RemoveSensetive(formV)
			} else {
				formMap[k] += "," + desensitization.RemoveSensetive(formV)
			}
		}
	}
	logit.ReplaceMetaFields(ctx, logit.AutoField(transmitEntities.LogReqBody, formMap))
}