refactor:使用指定DNS彻底解决DNS缓存导致的问题

Util/checker.go

@@ -1,36 +1,23 @@
 package Util
 
 import (
-	"Mmx/Request"
-	"fmt"
+	"context"
 	"net"
-	"time"
 )
 
 type checker struct{}
 
 var Checker checker
 
-func (checker) NetOk(url string) bool {
-	if ip, err := net.LookupIP("www.msftconnecttest.com"); err != nil { //通过DNS确认是否在线
+func (checker) NetOk() bool {
+	r := &net.Resolver{ //指定DNS，防止本地DNS缓存影响
+		PreferGo: true,
+		Dial:     NetDailEr(),
+	}
+	if ip, err := r.LookupIP(context.Background(), "ip4", "www.msftconnecttest.com"); err != nil { //通过DNS确认是否在线
 		return false
 	} else if len(ip) == 0 || ip[0].String() != "13.107.4.52" {
 		return false
 	}
-
-	{ //有些路由器有DNS缓存，故进行进一步确认
-		body, err := Request.Get(url, map[string]string{
-			"callback": "jQuery1635413",
-			"_":        fmt.Sprint(time.Now().UnixNano()),
-		})
-		ErrHandler(err)
-		r, err := GetResult(body)
-		if err != nil {
-			ErrHandler(err)
-		}
-		if r != "ok" {
-			return false
-		}
-	}
 	return true
 }