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Topic: NodeMCU Webserver (Read 347 times) previous topic - next topic


Hello, I need some help with nodemcu webserver code. I want to submit data from web page form to arduino sketch and the response from sketch to html page. I adopted code from some library example and trying to modifying according to my need. (In code i have changed variables, code is not ok just posting you people to understand the flow. sorry :)

HTML File:

Code: [Select]
<meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no" />

<span id="cmd"></span>

<div style='text-align:left;display:inline-block;width:150px;padding:1px'>

<form id="yform" onsubmit="return transmit(this)">

<button name="led1" value="on">Relay 1 On</button>
<button name="led1" value="off">Relay 1 Off</button>
<button name="led2" value="on">Relay 2 On</button>
<button name="led2" value="off">Relay 2 Off</button>
<button name="led3" value="on">Relay 3 On</button>
<button name="led3" value="off">Relay 3 Off</button>
<button name="led4" value="on">Relay 4 On</button>
<button name="led4" value="off">Relay 4 Off</button>
<button name="led5" value="on">Relay 5 On</button>
<button name="led5" value="off">Relay 5 Off</button>
<button name="led6" value="on">Relay 6 On</button>
<button name="led6" value="off">Relay 6 Off</button>
<button name="led7" value="on">Relay 7 On</button>
<button name="led7" value="off">Relay 7 Off</button>
<button name="led8" value="on">Relay 8 On</button>
<button name="led8" value="off">Relay 8 Off</button>


function g(i) { return document.getElementById(i) };

function transmit(f) {
if (!xhttp) { //prevent simultaneous requests
xhttp = new XMLHttpRequest();
xhttp.open("POST", "/api");
xhttp.send(f ? (new FormData(f)) : "");
xhttp.onreadystatechange = function () {
if (xhttp.readyState === XMLHttpRequest.DONE && xhttp.status === 200) {
var data = JSON.parse(xhttp.responseText);
g("cmd").innerHTML = data.cmd;
xhttp = null;

return false; //prevent form redirect


Arduino Sketch:
Code: [Select]
  //handles commands from webpage, sends live data in JSON format
  server.on("/api", []() {
    DEBUG_PRINT("server.on /api");
    if (server.hasArg("led")) {
      y = server.arg("led");
      DEBUG_PRINT("cmd: " + cmd);
    } //if

    //build json object of program data
    StaticJsonBuffer<200> jsonBuffer;
    JsonObject &json = jsonBuffer.createObject();
    json["cmd"] = cmd;

    char jsonchar[200];
    json.printTo(jsonchar); //print to char array, takes more memory but sends in one piece
    server.send(200, "application/json", jsonchar);

  }); //server.on api


No Reply...

Anyways I have changed the code and completed (no more jason).


and what works and what doesn't?
You can't write an Arduino sketch if you didn't learn programming. Not the language, but the concepts of programming - algorithms and data types.

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