macOS 開發 - 使用 CNCopySupportedInterfaces 獲取 WiFi ssid

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SSID 全稱 Service Set IDentifier

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CNCopySupportedInterfaces 核心代碼

- (void)testWifiInfo{

    NSDictionary *currentWifiInfo = nil;

    // 獲取當前的interface 數組
    // CNCopyCurrentNetworkInfo()
    CFArrayRef currentInterfaces = CNCopySupportedInterfaces();

    if (!currentInterfaces) {
        return ;
    }

    NSArray *interfaces = (__bridge NSArray *)(currentInterfaces);

    //無論是否開啓WiFi，都會顯示 WiFi 網卡 bsd name；無論是否連接有線，都不顯示有線網卡
    NSLog(@"interfaces : %@",interfaces);
    /*
    interfaces : (
    en1
    )
    */


    if (interfaces.count >0) {
        for (NSString *interfaceName in interfaces) {


            // 轉換類型，不改變引用計數
//            CFDictionaryRef dictRef = CNCopyCurrentNetworkInfo((__bridge CFStringRef)interfaceName);
//
//            if (dictRef) {
//                NSDictionary *networkInfo = (__bridge NSDictionary *)dictRef;
//
//                NSString *SSID = [networkInfo objectForKey:(__bridge NSString *)kCNNetworkInfoKeySSID];
//
//                NSString *BSSID = [networkInfoobjectForKey:(__bridge NSString *)kCNNetworkInfoKeyBSSID];
//
//                NSData *SSIDDATA = [networkInfoobjectForKey:(__bridge NSData *)kCNNetworkInfoKeySSIDData];
//
//                currentWifiInfo = @{@"SSID":SSID,
//                                    @"BSSID":BSSID,
//                                    @"SSIDDATA":SSIDDATA};

            }
        }

//    NSLog(@"currentWifiInfo = %@",currentWifiInfo);

}

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CNCopyCurrentNetworkInfo 在 iOS 可用，在 Mac 不可用

當在 Mac 上使用 CNCopyCurrentNetworkInfo 時，會提示：
'CNCopyCurrentNetworkInfo' is unavailable: not available on macOS

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前往查看 CNCopyCurrentNetworkInfo 定義時，會發現：

CFDictionaryRef __nullable
CNCopyCurrentNetworkInfo (CFStringRef interfaceName) __OSX_AVAILABLE_STARTING(__MAC_NA,__IPHONE_4_1);

注意這裏標記了 __MAC_NA

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