iOS Wifi开发

在开发wifi之前，有几个必须的步骤
1.添加Capability， Access WiFi Information

2.当前开发WiFi相关需要用户授权位置信息，你需要添加授权位置信息的代码，具体请查找CoreLocation相关的代码，当然不要忘记了在plist里要添加Privacy。

此时你可以获取到WiFi相关的数据了，不然会提示nehelper sent invalid result code [1] for Wi-Fi information request。

想要获取当前iphone设备连接的wifi的信息，下列代码返回的字典里包含了

+(NSDictionary *)currentWifiSSID
{
    NSArray *ifs = (__bridge id)CNCopySupportedInterfaces();
    id info = nil;
    for (NSString *ifnam in ifs) {
        info = (__bridge id)CNCopyCurrentNetworkInfo((__bridge CFStringRef)ifnam);
        if (info && [info count]) {
            break;
        }
    }
    NSDictionary *dctySSID = (NSDictionary *)info;
    return dctySSID;
}

返回的NSDictionary格式

{
    BSSID = "c:3a:fa:1:67:23";//设备的名字，类似于mac地址
    SSID = ABC;//WiFi的名字
    SSIDDATA = {length = 10, bytes = 0x53494e4f415353495354};
}

以下代码可以获取当前设备连接WiFi后所在局域网的ip地址

+ (nullable NSString*)vp_wifiIPAddress{
    NSString *address = nil;
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *temp_addr = NULL;
    int success = 0;
    // retrieve the current interfaces - returns 0 on success
    success = getifaddrs(&interfaces);
    if (success == 0) {
    // Loop through linked list of interfaces
    temp_addr = interfaces;
    while(temp_addr != NULL) {
    if(temp_addr->ifa_addr->sa_family == AF_INET) {
    // Check if interface is en0 which is the wifi connection on the iPhone
    if([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"]) {
    // Get NSString from C String
    address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];
    }
    }
    temp_addr = temp_addr->ifa_next;
    }
    }
    // Free memory
    freeifaddrs(interfaces);
    return address;
}