update readme with some EventSource examples

README.md

@@ -671,6 +671,57 @@ client->binary(flash_binary, 4);
 The server includes EventSource (Server-Sent Events) plugin which can be used to send short text events to the browser.
 Difference between EventSource and WebSockets is that EventSource is single direction, text-only protocol.
 
+### Setup Event Source on the server
+```cpp
+AsyncWebServer server(80);
+AsyncEventSource events("/events");
+
+void setup(){
+  // setup ......
+  events.onConnect([](AsyncEventSourceClient *client){
+    if(client->lastId()){
+      Serial.printf("Client reconnected! Last message ID that it gat is: %u\n", client->lastId());
+    }
+    //send event with message "hello!", id current millis
+    // and set reconnect delay to 1 second
+    client->send("hello!",NULL,millis(),1000);
+  });
+  server.addHandler(&events);
+  // setup ......
+}
+
+void loop(){
+  if(eventTriggered){ // your logic here
+    //send event "myevent"
+    client->send("my event content","myevent",millis());
+  }
+}
+```
+
+### Setup Event Source in the browser
+```javascript
+if (!!window.EventSource) {
+  var source = new EventSource('/events');
+
+  source.addEventListener('open', function(e) {
+    console.log("Events Connected");
+  }, false);
+
+  source.addEventListener('error', function(e) {
+    if (e.target.readyState != EventSource.OPEN) {
+      console.log("Events Disconnected");
+    }
+  }, false);
+
+  source.addEventListener('message', function(e) {
+    console.log("message", e.data);
+  }, false);
+
+  source.addEventListener('myevent', function(e) {
+    console.log("myevent", e.data);
+  }, false);
+}
+```
 
 ## Setting up the server
 ```cpp