iOS 检测网络状态自动判断认为提示网络改变

检测网络状态

在网络应用中，需要对用户设备的网络状态进行实时监控，目的是
让用户了解自己的网络状态，防止一些误会（比如怪应用无能）
根据用户的网络状态进行智能处理，节省用户流量，提高用户体验
WIFI\3G网络：自动下载高清图片
低速网络：只下载缩略图
没有网络：只显示离线的缓存数据

苹果官方提供了一个叫Reachability的示例程序，便于开发者检测网络状态
https://developer.apple.com/library/ios/samplecode/Reachability/Reachability.zip

Reachability的使用步骤
添加框架SystemConfiguration.framework

添加源代码

包含头文件

1	`<code` `class="hljs ruleslanguage">#import` `"Reachability.h"</code>`

抽取工具类

<code class="hljs objectivec">常见用法

// 是否WIFI

+ (BOOL) IsEnableWIFI {

return ([[Reachability reachabilityForLocalWiFi] currentReachabilityStatus] != NotReachable);

}

// 是否3G

+ (BOOL) IsEnable3G {

return ([[Reachability reachabilityForInternetConnectionen] currentReachabilityStatus] != NotReachable);

}

</code>

网络监控

<code class="hljs objectivec">[[NSNotificationCenter defaultCenter] addObserver:self

selector:@selector(reachabilityChanged:) name: kReachabilityChangedNotification object: nil];

self.netReachability = [Reachability reachabilityForInternetConnection];

[self.netReachability startNotifier];

- (void)dealloc

{

[self.netReachability stopNotifier];

[[NSNotificationCenter defaultCenter] removeObserver:self name:kReachabilityChangedNotification object:nil];

}

</code>

检测网络状态实例

NetWorkTool工具类

<code class="hljs java">#import <foundation foundation.h="">

@interface NetworkTool : NSObject

/**

* 是否WIFI

*/

+ (BOOL)isEnableWIFI;

/**

* 是否3G

*/

+ (BOOL)isEnable3G;

@end

</foundation></code>

<code class="hljs objectivec">#import "NetWorkTool.h"

#import "Reachability.h"

@implementation NetworkTool

// 是否WIFI

+ (BOOL)isEnableWIFI {

return ([[Reachability reachabilityForLocalWiFi] currentReachabilityStatus] != NotReachable);

}

// 是否3G

+ (BOOL)isEnable3G {

return ([[Reachability reachabilityForInternetConnection] currentReachabilityStatus] != NotReachable);

}

@end</code>

实现类

<code class="hljs objectivec">#import "ViewController.h"

#import "Reachability.h"

#import "NetworkTool.h"

@interface ViewController ()

@property (nonatomic, strong) Reachability *reachability;

@end

@implementation ViewController

- (void)viewDidLoad

{

[super viewDidLoad];

// 监听网络状态发生改变的通知

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(networkStateChange) name:kReachabilityChangedNotification object:nil];

// 获得Reachability对象

self.reachability = [Reachability reachabilityForInternetConnection];

// 开始监控网络

[self.reachability startNotifier];

}

- (void)dealloc

{

[self.reachability stopNotifier];

[[NSNotificationCenter defaultCenter] removeObserver:self];

}

- (void)networkStateChange

{

NSLog(@"网络状态改变了");

[self checkNetworkState];

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

[self checkNetworkState];

}</code>

<code class="hljs objectivec">#pragma mark - App应用程序网络类型改变就会调用

- (void)networkStateChange

{

if ([NetWorkTool isEnableWIFI]) {

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"温馨提示您" message:@"您现在网络环境为wifi！开始畅享吧！" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];

[alert show];

} else if ([NetWorkTool isEnable3G]) {

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"温馨提示您" message:@"您现在网络环境为3G/4G网络！" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];

[alert show];

} else {

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"温馨提示您" message:@"您当前没有可连的网络或已经掉线！" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];

[alert show];

}