iOS如何获得网络状态相关信息

1. 运营商信息: 直接使用CTTelephonyNetworkInfo的服务即可获得运营商的名字, 运营商编码等信息. easy!

-(NSString *)currentCarrierName{
    CTTelephonyNetworkInfo *telephonyInfo = [[CTTelephonyNetworkInfo alloc] init];
    CTCarrier *carrier = [telephonyInfo subscriberCellularProvider];
    return [[NSString alloc] initWithFormat:@"%@_%@_%@_%@", [carrier carrierName], [carrier mobileCountryCode], [carrier mobileNetworkCode], [carrier isoCountryCode]];
}

2. 当前网络类型(WiFi/4G) 信号强弱
   Google到的一个文章, 大致是访问statusBar的视图, 然后KVC访问该视图的属性, 从而得到想要的信息.
   文章没有提到如何获得信号强度, 不过, 顺着它的思路, 很快就找到了关键点:

类:**UIStatusBarDataNetworkItemView**, **UIStatusBarSignalStrengthItemView**
属性:**dataNetworkType**, **wifiStrengthBars**, **signalStrengthBars**

详细代码如下:

-(NSString *)currentNetworkType{
    NSArray *subviews = [[[[UIApplication sharedApplication] valueForKey:@"statusBar"] valueForKey:@"foregroundView"]subviews];
    
    NSNumber *dataNetworkItemView = nil;
    NSNumber *signalStrengthItemView = nil;
    for (id subview in subviews) {
        if([subview isKindOfClass:[NSClassFromString(@"UIStatusBarDataNetworkItemView") class]]) {
            dataNetworkItemView = subview;
        }
        if ([subview isKindOfClass:[NSClassFromString(@"UIStatusBarSignalStrengthItemView") class]]) {
            signalStrengthItemView = subview;
        }
        if (dataNetworkItemView && signalStrengthItemView) {
            break;
        }
    }
    
    if (!dataNetworkItemView) {
        return nil;
    }
    
    NSNumber *networkTypeNum = [dataNetworkItemView valueForKey:@"dataNetworkType"];
    NSNumber *wifiStrengthBars = [dataNetworkItemView valueForKey:@"wifiStrengthBars"];
    NSNumber *signalStrengthBars = [signalStrengthItemView valueForKey:@"signalStrengthBars"];
    if (!networkTypeNum) {
        return nil;
    }
    
    NSInteger networkType = [networkTypeNum integerValue];
    switch (networkType) {
        case 0:
            return @"No Service";
            break;
            
        case 1:
            return [[NSString alloc] initWithFormat:@"%@_%@", @"2G", signalStrengthBars];
            break;
            
        case 2:
            return [[NSString alloc] initWithFormat:@"%@_%@", @"3G", signalStrengthBars];
            break;
            
        case 3:
            return [[NSString alloc] initWithFormat:@"%@_%@", @"4G", signalStrengthBars];
            break;
            
        case 4:
            return [[NSString alloc] initWithFormat:@"%@_%@", @"LTE", signalStrengthBars];
            break;
            
        case 5:
            return [[NSString alloc] initWithFormat:@"%@_%@", @"WiFi", wifiStrengthBars];
            break;
        default:
            return [[NSString alloc] initWithFormat:@"%@_%@_%@", networkTypeNum, wifiStrengthBars, signalStrengthBars];
            break;
    }
}

3. 授之以渔
   我是怎么知道上面说的这些类有什么可以访问的属性的呢?
   答案是借助一个杰出的开源库YYModel.
   当然, 自己用OC的runtime方法写也是可以的, 只是没有用YYModel已经封装好的方法方便.

#import "YYModel.h"
//...
    YYClassInfo *info = [YYClassInfo classInfoWithClass:[signalStrengthItemView class]];
    NSLog(@"dataNetworkItemView ivars:%@", info.ivarInfos);
    NSLog(@"dataNetworkItemView properties:%@", info.propertyInfos);
    NSLog(@"dataNetworkItemView method:%@", info.methodInfos);

4. 结束:)