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Directory path . web .

HTML Document File : editor.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>editor</title>
    <link rel="stylesheet" href="/sitewide.css"><script src="/web/dhtml/color-theme/colors.js"></script>
</head>

<body>
    <button onclick="setBgFg('grey', 'yellow')">style 1</button>
    <button onclick="setBgFg('black', 'white')">style 2</button>
    <hr>
    
    <pre>// <a href="https://github.com/arkenidar/editor">https://github.com/arkenidar/editor</a>
// https://arkenidar.com/web/gh/editor/editor.html
// https://arkenidar.com/web/gh/editor/editor.js
</pre>

    <a href="https://gist.github.com/arkenidar/8a06a4dcf238fd3cfe1e81b580927362">lezioni, spunti, per questo
        editor-lavagna</a>
    <hr>

    <div id="page"><!-- your HTML here --></div>

    <hr>
    <button onclick="syncContent()">sincronizza</button>
    <label><input type="checkbox" id="autoSync" checked="">auto-sincronizza</label>
    <br>
    <button onclick="codeDecorations()">code decorations</button>
    <br>
    <!-- <textarea id="editor" cols="55" rows="30"></textarea> -->
    <pre id="editor" contenteditable="" style="border: 1px black solid; padding: 1em;"></pre>

    <style>
        .tag-inside {
            background-color: black;
            color: pink;
        }
    </style>

    <script src="editor.js"></script>

    <hr>

    <pre>

<textarea cols="55" rows="10">
<!-- --------------contatore------------------- -->

<button id=num onclick="this.textContent++">0</button>
<style>
#num{ min-width: 70px; height: auto; font-size: 60px; }
</style>
</textarea>

<textarea cols="55" rows="10" id="clicks">
<!-- --------------clicks---------------------- -->
<div id="buttons_section">
<button>previous</button> <button>next</button>
</div>

<script>
    var buttons = document.querySelectorAll("#buttons_section > button")

    for (var button of buttons)
        button.onclick = function (event) {
            var button = event.target
            alert("click received")
            alert(button.innerText)
        }

</script>
</textarea>

<textarea cols="55" rows="10">
<!-- ---------------somma---------------------- -->

<!-- interfaccia grafica in HTML -->
<input type="number" id="x" placeholder="numero x">
<input type="number" id="y" placeholder="numero y">
<div>il risultato è: <span id="risultato">0</span></div>
<!-- logica software in JavaScript -->
<script>
    x.oninput = calc; y.oninput = calc
    x.value = 0; y.value = 0
    function calc() { risultato.textContent = parseFloat(x.value) + parseFloat(y.value) }
    calc()
</script>
</textarea>

<textarea cols="55" rows="10">
<!-- ------------------percentuale------------- -->

<p>
inputs:
<input type="number" id="numero" placeholder="numero in input">

<input type="number" id="percentuale" placeholder="percentuale">
</p>

<p>
percentuale applicata:
<span id="risultato"></span>
</p>

<script>
    numero.oninput = applica
    percentuale.oninput = applica
    function applica() {
        risultato.textContent = numero.value * percentuale.value / 100
    }
</script>
</textarea>

</pre>

    <div><a href="."> go to main page. </a></div>

    <script src="/web/show-source.js"></script>

</body>

</html>