iOS 检测网络是否可以使用

#define kAppleUrlTocheckWifi @"http://captive.apple.com"
//检测网络是否可以使用
+(BOOL)isReach{

    // 1.将网址初始化成一个OC字符串对象
    NSString *newUrlStr = kAppleUrlTocheckWifi;

    // 2.构建网络URL对象, NSURL
    NSURL *url = [NSURL URLWithString:newUrlStr];
    // 3.创建网络请求
    NSURLRequest *request = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:3];
    // 创建同步链接
    NSURLResponse *response = nil;
    NSError *error = nil;
    NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];

    NSString* result1 = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];


    if ([result1 containsString:@"Success"])
    {
        NSLog(@"可以上网了");
        //   [PronetwayGeneralHandle shareHandle].NetworkCanUse = YES;
        return YES;
    }else {
        NSLog(@"未联网");
        //[self showNetworkStatus:@"未联网"];
        //   [PronetwayGeneralHandle shareHandle].NetworkCanUse = NO;
        return NO;
    }

}