如何简单地测试本地Wifi连接到IP，例如192.168.0.100的代码状态？

Question

您是否知道我是否可以简单地测试是否存在WIFI本地连接？例如，如果网址192.168.0.100可到达。我试图与可达性没有成功。它告诉我它已连接，但事实并非如此。

我想先来测试是否有本地WIFI连接，然后当我肯定是有联系的，启动该Web服务：

- (void)callWebService:(NSString *)url withBytes:(NSString *) bytes //GET 
{ 
     NSMutableURLRequest* request = [[NSMutableURLRequest alloc] init]; 
     NSString *url_string = [bytes stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]]; 
     [request setURL:[NSURL URLWithString:[url stringByAppendingString: url_string]]]; 
     [request setCachePolicy:NSURLRequestReloadIgnoringLocalCacheData]; 
     [request setTimeoutInterval:timeOut]; 
     NSURLConnection *connection = [NSURLConnection connectionWithRequest:request delegate:self]; //try NSURLSession 
     [connection start]; 
} 

在此先感谢。

Answer 1

NSURLConection有很多委托方法。请尝试以下之一：

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error 
{ 
    [self.download_connection cancel]; // optional depend on what you want to achieve. 
    self.download_connection = nil; // optional 

    DDLogVerbose(@"Connection Failed with error: %@", [error description]); 
} 

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response 
{ 
    NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *) response; 
    NSInteger state = [httpResponse statusCode]; 

    if (state >= 400 && state < 600) 
    { 
     // something wrong happen. 
     [self.download_connection cancel]; // optional 
     self.download_connection = nil; // optional 
    } 
} 

Answer 2

为了测试你必须使用苹果的Reachability互联网连接。使用枚举ReachableViaWiFi检查可访问性。

然后，你需要做你的服务器的ping。在您的didReceiveResponse方法中，您需要搜索服务器的成功范围。

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response 
{ 
    NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *) response; 
    NSInteger status = [httpResponse statusCode]; 

    if (status >= 200 && status <300) 
    { 
     // You are able to reach the server. Do something. 
    } 
} 

EDITED

“我试图与可达性没有成功”

你碰巧忘了通知可达性startNotifier？

Reachability *reachability = [Reachability reachabilityWithHostname:@"www.google.com"]; 

reachability.reachableBlock = ^(Reachability *reachability) { 
    NSLog(@"Network is reachable."); 
}; 

reachability.unreachableBlock = ^(Reachability *reachability) { 
    NSLog(@"Network is unreachable."); 
}; 

// Start Monitoring 
[reachability startNotifier];