引入 #import "AFNetworkReachabilityManager.h"

AFNetworkReachabilityManager *manager = [AFNetworkReachabilityManager sharedManager];

// 提示：要监控网络连接状态，必须要先调用单例的startMonitoring方法

[manager startMonitoring];

[manager setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {

if (status == -1) {

NSLog(@"未识别网络");

UIAlertController *alertview=[UIAlertController alertControllerWithTitle:@"未识别网络"

message:@"请打开设置→网络/Wi-Fi"

preferredStyle:UIAlertControllerStyleAlert];

UIAlertAction *cancel=[UIAlertAction actionWithTitle:@"取消"

style:UIAlertActionStyleCancel handler:nil];

UIAlertAction *defult = [UIAlertAction actionWithTitle:@"确定"

style:UIAlertActionStyleDefault

handler:^(UIAlertAction * _Nonnull action) {

}];

[alertview addAction:cancel];

[alertview addAction:defult];

[self presentViewController:alertview animated:YES completion:nil];

}

if (status == 0) {

NSLog(@"未连接网络");

UIAlertController *alertview=[UIAlertController alertControllerWithTitle:@"未连接网络"

message:@"请打开设置-蜂窝移动网络/Wi-Fi"

preferredStyle:UIAlertControllerStyleAlert];

UIAlertAction *defult = [UIAlertAction actionWithTitle:@"确定"

style:UIAlertActionStyleDefault

handler:^(UIAlertAction * _Nonnull action) {

}];

[alertview addAction:defult];

[self presentViewController:alertview animated:YES completion:nil];

}

if (status == 1) {

NSLog(@"3G/4G网络");

}

if (status == 2) {

NSLog(@"Wifi网络");

}

}];