Progressbar creare una barra di avanzamento

https://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_progressbar_3

<!DOCTYPE html>
<html>
<style>
#myProgress {
  width: 100%;
  background-color: #ddd;
}

#myBar {
  width: 1%;
  height: 30px;
  background-color: #4CAF50;
}
</style>
<body>

<h1>JavaScript Progress Bar</h1>

<br>
<button onclick="move()">Click Me</button>

</body>
</html>

' oppure con la scritta della percentuale visibile

<!DOCTYPE html>
<html>
<style>
#myProgress {
  width: 100%;
  background-color: #ddd;
}

#myBar {
  width: 10%;
  height: 30px;
  background-color: #4CAF50;
  text-align: center;
  line-height: 30px;
  color: white;
}
</style>
<body>

<h1>JavaScript Progress Bar</h1>

</body>
</html>

https://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_progressbar_3

<!DOCTYPE html>
<html>
<style>
#myProgress {
width: 100%;
background-color: #ddd;
}

#myBar {
width: 1%;
height: 30px;
background-color: #4CAF50;
}
</style>
<body>

<h1>JavaScript Progress Bar</h1>

<div id="myProgress">
<div id="myBar"></div>
</div>

<br>
<button onclick="move()">Click Me</button>

<script>
function move() {
var elem = document.getElementById("myBar");
var width = 1;
var id = setInterval(frame, 10);
function frame() {
if (width >= 100) {
clearInterval(id);
} else {
width++;
elem.style.width = width + '%';
}
}
}
</script>

</body>
</html>

' oppure con la scritta della percentuale visibile

<!DOCTYPE html>
<html>
<style>
#myProgress {
width: 100%;
background-color: #ddd;
}

#myBar {
width: 10%;
height: 30px;
background-color: #4CAF50;
text-align: center;
line-height: 30px;
color: white;
}
</style>
<body>

<h1>JavaScript Progress Bar</h1>

<div id="myProgress">
<div id="myBar">10%</div>
</div>

</body>
</html>