ios 判断网络是否可用工具类

//
// NetTool.m
// MusicLove
//
// Created by niuxinghua on 15/2/10.
// Copyright (c) 2015年 Hjojo. All rights reserved.
//

#import "NetTool.h"
@implementation NetTool
+(BOOL) isNetworkEnabled
{
BOOL bEnabled =
FALSE;
NSString *url =
@"www.baidu.com";
SCNetworkReachabilityRef ref =
SCNetworkReachabilityCreateWithName(NULL, [url
UTF8String]);
SCNetworkReachabilityFlags flags;

bEnabled = SCNetworkReachabilityGetFlags(ref, &flags);

CFRelease(ref);
if (bEnabled) {
// kSCNetworkReachabilityFlagsReachable：能够连接网络
// kSCNetworkReachabilityFlagsConnectionRequired：能够连接网络，但是首先得建立连接过程
// kSCNetworkReachabilityFlagsIsWWAN：判断是否通过蜂窝网覆盖的连接，比如EDGE，GPRS或者目前的3G.主要是区别通过WiFi的连接。
BOOL flagsReachable = ((flags & kSCNetworkFlagsReachable) !=
0);
BOOL connectionRequired = ((flags & kSCNetworkFlagsConnectionRequired) !=
0);
BOOL nonWiFi = flags & kSCNetworkReachabilityFlagsTransientConnection;
bEnabled = ((flagsReachable && !connectionRequired) || nonWiFi) ?
YES : NO;
}

return bEnabled;
}@end