javascript - Creating Circles(div) and appending it to div#canvas -

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i trying create new circles pen hovers on window. having issues cannot add circles page. hovers around. how able modify code add circles hovers.

<!doctype html>  <html>  <head>      <title> javascript environment: project </title>      <meta charset="utf-8">      <style>          html, body {              width: 100%;              height: 100%;              margin: 0px;              padding: 0px;          }          #canvas {              background-color: yellow;              width: 100%;              height: 100%;          }          .pen {              position: absolute;              background-color: lightblue;              width: 10px;              height: 10px;              border-radius: 5px;          }      </style>      <script>          window.onload = function() {              function circle(x, y) {                  this.x = x;                  this.y = y;              }              var canvas = document.getelementbyid("canvas");                canvas.onmousedown = function() {                  mousedown();              };              canvas.onmouseup = function() {                  mouseup()              };              canvas.onmousemove = function() {                  mousemove(event)              };              function mousedown (){                  console.log ("mouse down");              }              function mouseup (){                  console.log ("mouse up");              }              function mousemove(e) {                  var canvas = document.getelementbyid("canvas");                  var pen = document.createelement("div");                  var x = e.clientx;                  var y = e.clienty;                  var coor = "coordinates: (" + x + "," + y + ")";                  pen.setattribute("class", "pen");                  pen.style.left = x + "px";                  pen.style.top = y + "px";                  document.getelementbyid("canvas").innerhtml = coor;                  canvas.appendchild(pen);                  addcircles(x, y);                    console.log("location @ " + x + " : " + y);                }              function addcircles(x, y) {                  var canvas = document.getelementbyid("canvas");                  var circle = document.createelement("div");                  circle.setattribute("class", "pen");                  circle.style.left = x + "px";                  circle.style.top = y + "px";                  canvas.appendchild(circle);                }              canvas.addeventlistener("mousemove", mousemove, false);          };      </script>  </head>  <body>  <div id="canvas"></div>  </body>  </html>

the problem in line document.getelementbyid("canvas").innerhtml = coor;

try adding span <span id="canvastext"></span> inside of canvas div , changing above line document.getelementbyid("canvastext").innerhtml = coor;.

as stands, "reset" contents of canvas every time mouse moves, circles instantly removed it. reset span inside canvas keep circles around.


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