Da sie cos takiego zrobic tzn. sprawdzic tekst (chociaz wydaje mi sie to dosyc dziwne) i po co?
Z textarea dostaniesz ciag znakow i przez includes() mozna sprawdzic czy zawiera ciag '<hr id="system-read" >'
<!DOCTYPE html>
<html>
<head>
<meta charset='utf-8'>
<meta http-equiv='X-UA-Compatible' content='IE=edge'>
<title>Text Area</title>
<meta name='viewport' content='width=device-width, initial-scale=1'>
</head>
<body>
<textarea id='text' rows='10' cols='50'></textarea>
<button id='check-btn'>sprawdz</button>
<p id='result'>.....</p>
<script>
const checkBtn = document.querySelector('#check-btn')
const result = document.querySelector('#result')
const text = document.querySelector('#text')
checkH1 = () => {
if (text.value.includes('<hr id="system-read">')){
result.innerHTML = 'jest'
} else {
result.innerHTML = 'nie ma'
}
}
checkBtn.addEventListener('click',checkH1);
</script>
</body>
</html>