golang 获取本机内外网IP

获取本地内网ip

import (
	"net"
)

// LocalIPs return all non-loopback IPv4 addresses
func LocalIPv4s() ([]string, error) {
	var ips []string
	addrs, err := net.InterfaceAddrs()
	if err != nil {
		return ips, err
	}

	for _, a := range addrs {
		if ipnet, ok := a.(*net.IPNet); ok && !ipnet.IP.IsLoopback() && ipnet.IP.To4() != nil {
			ips = append(ips, ipnet.IP.String())
		}
	}

	return ips, nil
}

// GetIPv4ByInterface return IPv4 address from a specific interface IPv4 addresses
func GetIPv4ByInterface(name string) ([]string, error) {
	var ips []string

	iface, err := net.InterfaceByName(name)
	if err != nil {
		return nil, err
	}

	addrs, err := iface.Addrs()
	if err != nil {
		return nil, err
	}

	for _, a := range addrs {
		if ipnet, ok := a.(*net.IPNet); ok && !ipnet.IP.IsLoopback() && ipnet.IP.To4() != nil {
			ips = append(ips, ipnet.IP.String())
		}
	}

	return ips, nil
}

---

获取本机外网ip

package main
import (
    "net"
    "fmt"
    "strings"
)
func main() {
    conn, err := net.Dial("udp", "google.com:80")
    if err != nil {
        fmt.Println(err.Error())
        return
    }
    defer conn.Close()
    fmt.Println(strings.Split(conn.LocalAddr().String(), ":")[0])
}