I'm trying to limit the number of entered unicode characters in a textarea to 500.
When I try to post the form and get the textarea content to check its length in the back-end, I get a double length, meaning the value I get from strlen is twice the number of the inputted characters.
What is the problem here?
<textarea id="ArticleSummary" name="ArticleSummary" rows="4" maxlength="500">
<?php echo $Summary; ?></textarea>
$Summary = trim( $_POST['ArticleSummary'] );
echo strlen($Summary);
unicode characters take 2 bytes each and strlen returns the number of bytes in the string, you can transform it to unicode characters and check the length.
I don't know where from you are taking variable $Summary;but if it is longer than your required 500 signs it will be sent as is. Example code below:
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<?php empty($_POST['ArticleSummary']) or var_dump(mb_strlen($_POST['ArticleSummary']));?>
<form method="POST" action="">
<?php $text = '123456789'; ?>
<textarea id="ArticleSummary" name="ArticleSummary" rows="4" maxlength="5"><?php echo $text;?></textarea>
<input value="submit" type="submit" />
</form>
</body>
</html>
~ </div>