android怎么判断网络连接

在 Android 中,您可以使用以下几种方法来判断网络连接状态:

1. 使用 ConnectivityManager 类:

```java

ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);

NetworkInfo activeNetwork = cm.getActiveNetworkInfo();

boolean isConnected = activeNetwork != null && activeNetwork.isConnectedOrConnecting();

```

2. 使用 NetworkInfo 类:

```java

ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);

NetworkInfo networkInfo = cm.getNetworkInfo(ConnectivityManager.TYPE_WIFI);

boolean isWifiConnected = networkInfo != null && networkInfo.isConnected();

networkInfo = cm.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);

boolean isMobileConnected = networkInfo != null && networkInfo.isConnected();

```

3. 使用 Internet 连通性检查:

```java

public static boolean isInternetAvailable(Context context) {

try {

URL url = new URL("http://www.google.com");

HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

urlConnection.setConnectTimeout(3000);

urlConnection.connect();

return urlConnection.getResponseCode() == 200;

} catch (Exception e) {

return false;

}

}

```

4. 使用 Ping 检查:

```java

public static boolean isHostAvailable(String hostname) {

try {

Process process = Runtime.getRuntime().exec("/system/bin/ping -c 1 " + hostname);

int exitValue = process.waitFor();

return (exitValue == 0);

} catch (IOException | InterruptedException e) {

return false;

}

}

```

以上是一些常见的判断网络连接状态的方法,可以根据具体需求选择合适的方式来实现。需要注意的是,在使用这些方法时需要考虑权限的申请和设备上的网络状态,以确保获取的信息是准确的。