Android检查设备是否联网

	public static boolean isConnect(Context context) {
		ConnectivityManager connectionManager = (ConnectivityManager) context
				.getSystemService(Context.CONNECTIVITY_SERVICE);
		if (connectionManager != null) {
			NetworkInfo info = connectionManager.getActiveNetworkInfo();
			if (info != null && info.isConnected()) {
				if (info.getState() == NetworkInfo.State.CONNECTED) {
					return true;
				}
			}
		}
		return false;
	}