[Plugin: Contact Form 7] Set character limit in textarea

Add this code into your active theme’s functions.php file:

add_filter( 'wpcf7_validate_textarea', 'character_length_validation_filter', 11, 2 );
add_filter( 'wpcf7_validate_textarea*', 'character_length_validation_filter', 11, 2 );

function character_length_validation_filter( $result, $tag ) {
	$name = $tag['name'];

	if ( ! $result['valid'] )
		return $result;

	if ( 400 < strlen( $_POST[$name] ) ) {
		$result['valid'] = false;
		$result['reason'][$name] = "Too long.";
	}

	return $result;
}

This way, you’ll get a validation error when you enter more than 400 characters into textarea.

Thanks so much for the quick reply. I add the above code at the end of the functions.php file and got this error:

Parse error: syntax error, unexpected T_FUNCTION, expecting T_STRING or T_VARIABLE or ‘$’ in /html/wp-content/themes/machine/functions.php on line 283

Am I putting it in the right place? Should it go before or after a certain code segment?

Also, is there a way to restrict the character limit to only one of the textarea fields? For example, if I have textarea A that should be 400 or less and textarea B that can be more than 400, is there a way to distinguish them?

Thanks again for all your help!

Pyson, could you share how you limit the characters in a text box? Looking to do the standard 3 box phone number setup with 3-3-4 characters set for each box so it automatically jumps to the next box after 3 characters are entered, etc.

Thanks for any guidance.

Thank you Takayuki Miyoshi !