如何使用SignalR将消息从服务器端发送到客户端？

using Microsoft.AspNetCore.SignalR;
using System.Threading.Tasks;

public class ChatHub : Hub
{
    public async Task SendMessage(string user, string message)
    {
        await Clients.All.SendAsync("ReceiveMessage", user, message);
    }
}

using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.DependencyInjection;

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddSignalR();
    }

    public void Configure(IApplicationBuilder app)
    {
        app.UseRouting();
        app.UseEndpoints(endpoints =>
        {
            endpoints.MapHub<ChatHub>("/chatHub");
        });
    }
}

<script src="/path/to/signalr.js"></script>

var connection = new signalR.HubConnectionBuilder()
    .withUrl("/chatHub")
    .build();

connection.on("ReceiveMessage", function(user, message) {
    // 处理接收到的消息
});

connection.start().then(function() {
    // 连接成功后的操作
}).catch(function(error) {
    // 连接失败后的操作
});

public class ChatHub : Hub
{
    public async Task SendMessage(string user, string message)
    {
        await Clients.All.SendAsync("ReceiveMessage", user, message);
    }
}