renderEngine.js

var j = 0;
// Function for live Rendering
function update(i) {
  if (i == 0) {
    let htmlCode = document.getElementById("htmlCode").value;
    let cssCode = document.getElementById("cssCode").value;
    let javascriptCode = document.getElementById("jsCode").value;
    let text =
      htmlCode +
      "<style>" +
      cssCode +
      "</style>" +
      "<scri" +
      "pt>" +
      javascriptCode +
      "</scri" +
      "pt>";
    let iframe = document.getElementById("viewer").contentWindow.document;
    iframe.open();
    iframe.write(text);
    iframe.close();
  } else if (i == 1) {
    let htmlCode = document.getElementById("htmlCode").value;
    let html = htmlCode.slice(0, htmlCode.length);
    document.getElementById("htmlCode").value = html;
    j = 1;
  }
}