var source=new EventSource("demo_sse.php");
source.onmessage=function(event) { document.getElementById("result").innerHTML+=event.data + "<br />"; };

//php方式
<?php
header('Content-Type: text/event-stream'); header('Cache-Control: no-cache'); $time = date('r'); echo "data: The server time is: {$time}\n\n"; flush(); ?> //asp方式 <% Response.ContentType="text/event-stream" Response.Expires=-1 Response.Write("data: " & now()) Response.Flush() %>

• 把报头 "Content-Type" 设置为 "text/event-stream"
• 规定不对页面进行缓存
• 输出发送日期(始终以 "data: " 开头)
• 向网页刷新输出数据

public void Subscribe(){HttpContext.Response.ContentType = "text/event-stream";HttpContext.Response.CacheControl = "no-cache"; HttpContext.Response.Write("data:" + DateTime.Now.ToString()+ "\n\n"); HttpContext.Response.Flush(); }

public class PublishService{private static IDictionary<string, HttpResponseBase> contexts = new Dictionary<string, HttpResponseBase>(); public static void AddHttpContext(HttpContextBase context) { var token = context.GetToken(”CookieName“); if (!contexts.Keys.Contains(token)) contexts.Add(token, context.Response); } private static void Publish() { foreach (var context in contexts.Values) { context.ContentType = "text/event-stream"; context.CacheControl = "no-cache"; msg = GetData(context.GetToken("CookieName")); context.Write("data:" + msg + "\n\n"); context.Flush(); } }         public void Subscribe()         {             PublishService.AddHttpContext(HttpContext);             PublishService.Publish();         } }

public void Subscribe(){var data = GetData();HttpContext.Response.ContentType = "text/event-stream"; HttpContext.Response.CacheControl = "no-cache"; HttpContext.Response.Write("data:" + data + "\n\n"); HttpContext.Response.Flush(); }