Android 获取WIFI SSID的两种方式

方式一：

    public String getSSID() {
        WifiManager wm = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);
        if (wm != null) {
            WifiInfo winfo = wm.getConnectionInfo();
            if (winfo != null) {
                String s = winfo.getSSID();
                if (s.length() > 2 && s.charAt(0) == '"' && s.charAt(s.length() - 1) == '"') {
                    return s.substring(1, s.length() - 1);
                }
            }
        }
        return "";
    }

方式二：

    private String getMacAddress(){
        ConnectivityManager cm = (ConnectivityManager) MainActivity.this.getApplicationContext().getSystemService(Service.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetworkInfo = cm.getActiveNetworkInfo();
        String extraInfo = activeNetworkInfo.getExtraInfo();
        return extraInfo;
    }