How to send data in response to HTTP get request from ESP8266?

Question

I'm trying to control some RGB LEDs with ESP8266. I have built an HTML page to set the color and send the RGB color code to the ESP using HTTP get request. Everything works as expected. I just want to send an HTTP get request to the ESP and ask what the current color is. But after a couple of hours of searching and trying I don't know how to send data in response to get request, I just can send HTTP ok code. I'm using jquery to send get command as below

$.get("http://192.168.4.1/rgb(120,50,60)", function(data,status){ 
 //I don't know how to send data fram ESP get it here.
});

this is the corresponding ESP response code written in Arduini IDE

WiFiClient client = server.available();
 if (client) {
 String req = client.readStringUntil('\r');
 client.print("HTTP/1.1 200 OK\r\n");
 client.print("Access-Control-Allow-Origin: *");
.
.
.

This is the HTTP header, How do I send some data(text)?

• dandavis: look at the webserver example. something like server.send(200, "text/plain", someStringOfContentHere); build up the string with the data you need.
• ahmadx87: Thak you for your input. To use send method I have to include ESP8266WebServer.h and modify my code. I think there should an easy way to send some text (like HTML markup) after the header.
• Gerben: After the last header you need to send two newlines (\r\n\r\n) and then send your data.
• ahmadx87: Thank you @Gerben! I spent hours searching but no success. It worked like a charm.

Answer 1

@Gerben answered my question in a comment all credit goes to him. I retype it here maybe it helps someone in the future.

I had to send two new line after setting up the header

//header
client.print("\r\n\r\n");
clinet.print("Hello, I'm comming from ESP!!");

And in jQuery I get it like this:

$.get("http://192.168.4.1/rgb(120,50,60)", function(data,status){ 
 var receivedData=data; //=Hello, I'm comming from ESP!!
});

It is simple but it may help some newbie like me.