我想用 ip 检查服务器是否在线,例如 74.125.71.104 (Google 的 ip)
//分配一个可达性对象
`struct sockaddr_in address;
address.sin_len = sizeof(address);
address.sin_family = AF_INET;
address.sin_port = htons(80);
address.sin_addr.s_addr = inet_addr("74.125.71.104");`
Reachability *reach = [Reachability reachabilityWithAddress:&address];
但那些不工作。
当我更改为
reachabilityWithHostname
时,它正在工作。 最佳答案
请导入#include <arpa/inet.h>
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotification object:nil];
struct sockaddr_in address;
address.sin_len = sizeof(address);
address.sin_family = AF_INET;
address.sin_port = htons(8080);
address.sin_addr.s_addr = inet_addr("216.58.199.174"); //google ip
self.internetReachability = [Reachability reachabilityWithAddress:&address];
[self.internetReachability startNotifier];
[self updateInterfaceWithReachability:self.internetReachability];
编辑
根据您的评论,不会调用您的可达性块。我总是使用对可达性块不太了解的通知。所以我更喜欢使用通知如下。
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotification object:nil];
struct sockaddr_in address;
address.sin_len = sizeof(address);
address.sin_family = AF_INET;
address.sin_port = htons(8080);
address.sin_addr.s_addr = inet_addr("216.58.199.174");
self.internetReachability = [Reachability reachabilityWithAddress:&address];
[self.internetReachability startNotifier];
[self updateInterfaceWithReachability:self.internetReachability];
现在,每当您的 Internet 状态发生变化时,reachabilityChanged 方法都会通过可达性实例触发 :)
- (void) reachabilityChanged:(NSNotification *)note {
Reachability* curReach = [note object];
[self updateInterfaceWithReachability:curReach];
}
最后将 updateInterfaceWithReachability 实现为
- (void)updateInterfaceWithReachability:(Reachability *)reachability {
NetworkStatus netStatus = [reachability currentReachabilityStatus];
switch (netStatus)
{
case NotReachable: {
//not reachable
}
break;
case ReachableViaWWAN:
case ReachableViaWiFi: {
//reachable via either 3g or wifi
}
break;
}
}
希望这可以帮助。
关于ios - reachabilityWithAddress 在 Objective C 编程中不起作用,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/37742367/