android - 如何在android中获取连接到同一个Wi-Fi网络的系统的所有IP地址

Question

谁能告诉我如何在 Android 中以编程方式查找连接到同一网络的所有系统的 IP 地址。 DHCPInfo 类仅提供分配给我们的 android 设备的 IP 地址，而不提供连接到同一网络的其他设备的 IP 地址。如何获取连接到同一网络的其他设备的ipaddress？

Answer 1

首先通过这个获取主机ip

public String   s_dns1 ;
   public String   s_dns2;     
   public String   s_gateway;  
   public String   s_ipAddress;    
   public String   s_leaseDuration;    
   public String   s_netmask;  
   public String   s_serverAddress;
   TextView info;
   DhcpInfo d;
   WifiManager wifii;

    wifii = (WifiManager) getSystemService(Context.WIFI_SERVICE);
        d = wifii.getDhcpInfo();

        s_dns1 = "DNS 1: " + String.valueOf(d.dns1);
        s_dns2 = "DNS 2: " + String.valueOf(d.dns2);
        s_gateway = "Default Gateway: " + String.valueOf(d.gateway);
        s_ipAddress = "IP Address: " + String.valueOf(d.ipAddress);
        s_leaseDuration = "Lease Time: " + String.valueOf(d.leaseDuration);
        s_netmask = "Subnet Mask: " + String.valueOf(d.netmask);
        s_serverAddress = "Server IP: " + String.valueOf(d.serverAddress);

d.dns1是主机ip

现在通过这个获取连接的ips

String connections = "";
        InetAddress host;
        try
        {
            host = InetAddress.getByName(intToIp(d.dns1));
            byte[] ip = host.getAddress();

            for(int i = 1; i <= 254; i++)
            {
                ip[3] = (byte) i;
                InetAddress address = InetAddress.getByAddress(ip);
                if(address.isReachable(100))
                {
                    System.out.println(address + " machine is turned on and can be pinged");
                    connections+= address+"\n";
                }
                else if(!address.getHostAddress().equals(address.getHostName()))
                {
                    System.out.println(address + " machine is known in a DNS lookup");
                }

            }
        }
        catch(UnknownHostException e1)
        {
            e1.printStackTrace();
        }
        catch(IOException e)
        {
            e.printStackTrace();
        }
       System.out.println(connections);

intToIp

public String intToIp(int i) {
        return (i & 0xFF) + "." +
                ((i >> 8 ) & 0xFF) + "." +
                ((i >> 16) & 0xFF) + "." +
                ((i >> 24) & 0xFF);
    }