C# UdpClient无法发送多播UDP数据包

using System;
using System.Net;
using System.Net.Sockets;

class Program
{
    static void Main()
    {
        // 创建一个UDP Socket
        Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

        // 设置Socket为多播模式
        socket.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.MulticastLoopback, true);

        // 加入多播组
        IPAddress multicastAddress = IPAddress.Parse("组播IP地址");
        socket.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddMembership, new MulticastOption(multicastAddress));

        // 绑定本地IP和端口
        IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Any, 1234);
        socket.Bind(localEndPoint);

        // 发送数据
        byte[] data = System.Text.Encoding.UTF8.GetBytes("Hello, multicast!");
        IPEndPoint remoteEndPoint = new IPEndPoint(multicastAddress, 1234);
        socket.SendTo(data, remoteEndPoint);

        // 关闭Socket
        socket.Close();
    }
}