我想检查一下我是否可以在iOS上使用Cocoa Touch库或在macOS上使用Cocoa库连接互联网。
我想出了一个方法来做这个使用NSURL。我的方法似乎有点不可靠(因为即使谷歌也可能有一天宕机，依赖第三方似乎很糟糕)，虽然如果谷歌没有响应，我可以检查其他一些网站的响应，但这似乎是浪费和不必要的应用程序开销。
- (BOOL)connectedToInternet {
NSString *URLString = [NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://www.google.com"]];
return ( URLString != NULL ) ? YES : NO;
}
是我做得不好，(更不用说stringWithContentsOfURL已弃用在iOS 3.0和macOS 10.4)，如果是这样，有什么更好的方法来实现这一点?
当前回答
苹果提供了一个示例应用程序，它正是这样做的:
可达性
其他回答
检查Internet连接的可用性(iOS) Xcode 8, Swift 3.0
这是一个简单的方法来检查网络可用性，如我们的设备是否连接到任何网络。我已经成功地将其翻译为Swift 3.0，这里是最终的代码。现有的Apple Reachability类和其他第三方库似乎太复杂了，无法翻译到Swift中。 这适用于3G、4G和WiFi连接。 不要忘记在你的项目构建器中添加“SystemConfiguration.framework”。
//Create new swift class file Reachability in your project.
import SystemConfiguration
public class InternetReachability {
class func isConnectedToNetwork() -> Bool {
var zeroAddress = sockaddr_in(sin_len: 0, sin_family: 0, sin_port: 0, sin_addr: in_addr(s_addr: 0), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0))
zeroAddress.sin_len = UInt8(sizeofValue(zeroAddress))
zeroAddress.sin_family = sa_family_t(AF_INET)
let defaultRouteReachability = withUnsafePointer(&zeroAddress) {
SCNetworkReachabilityCreateWithAddress(nil, UnsafePointer($0)).takeRetainedValue()
}
var flags: SCNetworkReachabilityFlags = 0
if SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags) == 0 {
return false
}
let isReachable = (flags & UInt32(kSCNetworkFlagsReachable)) != 0
let needsConnection = (flags & UInt32(kSCNetworkFlagsConnectionRequired)) != 0
return isReachable && !needsConnection
}
}
// Check network connectivity from anywhere in project by using this code.
if InternetReachability.isConnectedToNetwork() == true {
print("Internet connection OK")
} else {
print("Internet connection FAILED")
}
只有Reachability类已经更新。你现在可以使用:
Reachability* reachability = [Reachability reachabilityWithHostName:@"www.apple.com"];
NetworkStatus remoteHostStatus = [reachability currentReachabilityStatus];
if (remoteHostStatus == NotReachable) { NSLog(@"not reachable");}
else if (remoteHostStatus == ReachableViaWWAN) { NSLog(@"reachable via wwan");}
else if (remoteHostStatus == ReachableViaWiFi) { NSLog(@"reachable via wifi");}
关于Reachability的iOS 5版本是darkseed/Reachability.h。不是我的!=)
迅捷5号，我是阿拉莫火，主持人
// Session reference
var alamofireSessionManager: Session!
func checkHostReachable(completionHandler: @escaping (_ isReachable:Bool) -> Void) {
let configuration = URLSessionConfiguration.default
configuration.timeoutIntervalForRequest = 1
configuration.timeoutIntervalForResource = 1
configuration.requestCachePolicy = .reloadIgnoringLocalCacheData
alamofireSessionManager = Session(configuration: configuration)
alamofireSessionManager.request("https://google.com").response { response in
completionHandler(response.response?.statusCode == 200)
}
}
// Using
checkHostReachable() { (isReachable) in
print("isReachable:\(isReachable)")
}
还有另一种使用iPhone SDK检查互联网连接的方法。
尝试为网络连接实现以下代码。
#import <SystemConfiguration/SystemConfiguration.h>
#include <netdb.h>
/**
Checking for network availability. It returns
YES if the network is available.
*/
+ (BOOL) connectedToNetwork
{
// Create zero addy
struct sockaddr_in zeroAddress;
bzero(&zeroAddress, sizeof(zeroAddress));
zeroAddress.sin_len = sizeof(zeroAddress);
zeroAddress.sin_family = AF_INET;
// Recover reachability flags
SCNetworkReachabilityRef defaultRouteReachability =
SCNetworkReachabilityCreateWithAddress(NULL, (struct sockaddr *)&zeroAddress);
SCNetworkReachabilityFlags flags;
BOOL didRetrieveFlags = SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags);
CFRelease(defaultRouteReachability);
if (!didRetrieveFlags)
{
printf("Error. Could not recover network reachability flags\n");
return NO;
}
BOOL isReachable = ((flags & kSCNetworkFlagsReachable) != 0);
BOOL needsConnection = ((flags & kSCNetworkFlagsConnectionRequired) != 0);
return (isReachable && !needsConnection) ? YES : NO;
}
