gaols · June 12, 2022 13:25
diff --git a/codeEditor.html b/codeEditor.html
 <!DOCTYPE html>
 <html lang='en'>
 	<head>
 	    <meta charset='utf-8'>
 	    <meta name='description' content='line numbering textarea editor demo'>
 	    <meta name='keywords' content='line numbering,textarea,editor'>
 	    <meta name='viewport' content='width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0' />
 	    <meta http-equiv='X-UA-Compatible' content='IE=Edge,chrome=1' />  
 	    <meta http-equiv='Content-Language' content='en' />
  		<title>Line Numbering to Textarea Demo</title>
  		<style>
 	  		html, body {
  				margin:0;
  				padding:0;
  				width:100vw;
  				height:100vh;
  				overflow:hidden;
  				font-family: lucida console, courier new, courier, monospace;
  				font-size: 1rem;
    			font-weight: 400;
 	  		}

 			#codeEditor, #lineCounter {
 				font-family: lucida console, courier new, courier, monospace;
 				margin: 0;
 			    padding: 10px 0;
 			    height: 75vh;
 			    border-radius: 0;
 			    resize: none;
 			    font-size: 16px;
 			    line-height: 1.2;
 			    outline: none;
 			    -moz-box-sizing: border-box;
 			    -webkit-box-sizing: border-box;
 			    box-sizing: border-box;
 			}
 			#codeEditor {
 			    padding-left: calc(3.5rem + 5px);
 			    width:100%;
 			    /* Determine appearance of code editor */
 			    background-color:#272822;
 			    border-color:#272822;
 			    color:#ffffff;
 			}
 			#lineCounter {
 			    display: flex;
 			    border-color: transparent;
 			    overflow-y: hidden;
 			    text-align: right;
 			    box-shadow: none;
 			    color: #707070;
 			    background-color: #d8d8d8;
 			    position: absolute;
 			    width: 3.5rem;
 			    /* Determine appearance of line counter */
 			    background-color:#3E3D32;
 			    border-color:#3E3D32;
 			    color:#928869;
 			}
 			#lineCounter:focus-visible,
 			#codeEditor:focus-visible {
 			    outline:none;
 			}
  		</style>
  		<noscript>You need to enable JavaScript to run this app.</noscript>
 	</head>
 	<body>
 		<h2>📝 Code Editor</h2>
 		<p><textarea id='lineCounter' wrap='off' readonly>1.</textarea><textarea id='codeEditor' wrap='off'></textarea></p>

 		<script>
 			var htmlTemplateStr = "<!DOCTYPE html>"
 			+"\n<html lang='en'>"
 			+"\n	<head>"
 			+"\n		<meta charset='utf-8'>"
 			+"\n		<title>Page Title</title>"
 			+"\n	<head>"
 			+"\n	<body>"
 			+"\n		<!-- CONTENT GOES HERE -->"
 			+"\n	</body>"
 			+"\n</html>";

 			var codeEditor = document.getElementById('codeEditor');
 			var lineCounter = document.getElementById('lineCounter');
 			
 			var lineCountCache = 0;
 			function line_counter() {
 		        var lineCount = codeEditor.value.split('\n').length;
 		        var outarr = new Array();
 		        if (lineCountCache != lineCount) {
 		            for (var x = 0; x < lineCount; x++) {
 		                outarr[x] = (x + 1) + '.';
 		            }
 		            lineCounter.value = outarr.join('\n');
 		        }
 		        lineCountCache = lineCount;
 			}

 			codeEditor.addEventListener('scroll', () => {
 				lineCounter.scrollTop = codeEditor.scrollTop;
 			    lineCounter.scrollLeft = codeEditor.scrollLeft;
 			});

 			codeEditor.addEventListener('input', () => {
 				line_counter();
 			});

 			codeEditor.addEventListener('keydown', (e) => {
 			    let { keyCode } = e;
 			    let { value, selectionStart, selectionEnd } = codeEditor;

 			    if (keyCode === 9) {  // TAB = 9
 			      e.preventDefault();
 			      codeEditor.value = value.slice(0, selectionStart) + '\t' + value.slice(selectionEnd);
 			      codeEditor.setSelectionRange(selectionStart+2, selectionStart+1)
 			    }
 		  	});

 		  	codeEditor.value = htmlTemplateStr;
 		  	line_counter();
 		</script>
 	</body>
 </html>
	<!DOCTYPE html>
	<html lang='en'>
	<head>
	<meta charset='utf-8'>
	<meta name='description' content='line numbering textarea editor demo'>
	<meta name='keywords' content='line numbering,textarea,editor'>
	<meta name='viewport' content='width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0' />
	<meta http-equiv='X-UA-Compatible' content='IE=Edge,chrome=1' />
	<meta http-equiv='Content-Language' content='en' />
	<title>Line Numbering to Textarea Demo</title>
	<style>
	html, body {
	margin:0;
	padding:0;
	width:100vw;
	height:100vh;
	overflow:hidden;
	font-family: lucida console, courier new, courier, monospace;
	font-size: 1rem;
	font-weight: 400;
	}

	#codeEditor, #lineCounter {
	font-family: lucida console, courier new, courier, monospace;
	margin: 0;
	padding: 10px 0;
	height: 75vh;
	border-radius: 0;
	resize: none;
	font-size: 16px;
	line-height: 1.2;
	outline: none;
	-moz-box-sizing: border-box;
	-webkit-box-sizing: border-box;
	box-sizing: border-box;
	}
	#codeEditor {
	padding-left: calc(3.5rem + 5px);
	width:100%;
	/* Determine appearance of code editor */
	background-color:#272822;
	border-color:#272822;
	color:#ffffff;
	}
	#lineCounter {
	display: flex;
	border-color: transparent;
	overflow-y: hidden;
	text-align: right;
	box-shadow: none;
	color: #707070;
	background-color: #d8d8d8;
	position: absolute;
	width: 3.5rem;
	/* Determine appearance of line counter */
	background-color:#3E3D32;
	border-color:#3E3D32;
	color:#928869;
	}
	#lineCounter:focus-visible,
	#codeEditor:focus-visible {
	outline:none;
	}
	</style>
	<noscript>You need to enable JavaScript to run this app.</noscript>
	</head>
	<body>
	<h2>📝 Code Editor</h2>
	<p><textarea id='lineCounter' wrap='off' readonly>1.</textarea><textarea id='codeEditor' wrap='off'></textarea></p>

	<script>
	var htmlTemplateStr = "<!DOCTYPE html>"
	+"\n<html lang='en'>"
	+"\n <head>"
	+"\n <meta charset='utf-8'>"
	+"\n <title>Page Title</title>"
	+"\n <head>"
	+"\n <body>"
	+"\n <!-- CONTENT GOES HERE -->"
	+"\n </body>"
	+"\n</html>";

	var codeEditor = document.getElementById('codeEditor');
	var lineCounter = document.getElementById('lineCounter');

	var lineCountCache = 0;
	function line_counter() {
	var lineCount = codeEditor.value.split('\n').length;
	var outarr = new Array();
	if (lineCountCache != lineCount) {
	for (var x = 0; x < lineCount; x++) {
	outarr[x] = (x + 1) + '.';
	}
	lineCounter.value = outarr.join('\n');
	}
	lineCountCache = lineCount;
	}

	codeEditor.addEventListener('scroll', () => {
	lineCounter.scrollTop = codeEditor.scrollTop;
	lineCounter.scrollLeft = codeEditor.scrollLeft;
	});

	codeEditor.addEventListener('input', () => {
	line_counter();
	});

	codeEditor.addEventListener('keydown', (e) => {
	let { keyCode } = e;
	let { value, selectionStart, selectionEnd } = codeEditor;

	if (keyCode === 9) { // TAB = 9
	e.preventDefault();
	codeEditor.value = value.slice(0, selectionStart) + '\t' + value.slice(selectionEnd);
	codeEditor.setSelectionRange(selectionStart+2, selectionStart+1)
	}
	});

	codeEditor.value = htmlTemplateStr;
	line_counter();
	</script>
	</body>
	</html>