using System.Net;

/// <summary>

/// 获得广播地址

/// </summary>

/// <param name="ipAddress">IP地址</param>

/// <param name="subnetMask">子网掩码</param>

/// <returns>广播地址</returns>

public static string GetBroadcast(string ipAddress, string subnetMask)

{

    byte[] ip = IPAddress.Parse(ipAddress).GetAddressBytes();

    byte[] sub = IPAddress.Parse(subnetMask).GetAddressBytes();

    // 广播地址=子网按位求反 再 或IP地址

    for (int i = 0; i < ip.Length; i++)

    {

        ip[i] = (byte)((~sub[i]) | ip[i]);

    }

    return new IPAddress(ip).ToString();

}