利用 SCNetworkReachability 取得網路服務狀態的方法

 

若要辨識網路的服務狀態，可以參考以下程式碼範例。

在開始之前首先要 import 兩個標頭檔並加入 SystemConfiguration.framework，加入的方法是在 Groups & Files 內的專案名稱上按下右鍵 > Add > Existing Frameworks，之後選擇需要的 framework 並 Add 即可。

#import <netinet/in.h>
#import <SystemConfiguration/SystemConfiguration.h>

//Create zero addy
struct sockaddr_in Addr;
bzero(&Addr, sizeof(Addr));
Addr.sin_len = sizeof(Addr);
Addr.sin_family = AF_INET;

//結果存至旗標中
SCNetworkReachabilityRef target = SCNetworkReachabilityCreateWithAddress(NULL, (struct sockaddr *) &Addr);
SCNetworkReachabilityFlags flags;
SCNetworkReachabilityGetFlags(target, &flags);


//將取得結果與狀態旗標位元做AND的運算並輸出
if (flags & kSCNetworkFlagsReachable) switch1.on = YES; else switch1.on = NO;
if (flags & kSCNetworkReachabilityFlagsIsWWAN) switch2.on = YES; else switch2.on = NO;
如果讀者有興趣，也可是著參考下列 iOS Library 的提供的旗標判斷。

(flags & kSCNetworkReachabilityFlagsIsWWAN)
(flags & kSCNetworkReachabilityFlagsReachable)

(flags & kSCNetworkReachabilityFlagsTransientConnection)
(flags & kSCNetworkReachabilityFlagsConnectionRequired)
(flags & kSCNetworkReachabilityFlagsConnectionOnTraffic)
(flags & kSCNetworkReachabilityFlagsInterventionRequired)
(flags & kSCNetworkReachabilityFlagsConnectionOnDemand)
(flags & kSCNetworkReachabilityFlagsIsLocalAddress)
(flags & kSCNetworkReachabilityFlagsIsDirect)