Untitled

<!DOCTYPE HTML>
<?php
if(isset($_POST['mail']))
	echo filter_var($_POST['mail'], FILTER_VALIDATE_EMAIL) ? "Poprawny" : "Niepoprawny";
?>
<html>
<body>
<form action="" method="post">
	<input type="text" name="mail">
	<input type="submit" value="Click">
</form>
</body>
</html>


<?php
function color($red, $green, $blue)
{
	$red %= 256;
	$green %= 256;
	$blue %= 256;

	$red = ($red <= 15) ? "0".dechex($red) : dechex($red);
	$green = ($green <= 15) ? "0".dechex($green) : dechex($green);
	$blue = ($blue <= 15) ? "0".dechex($blue) : dechex($blue);

	return "#".$red.$green.$blue;
}

if(isset($_POST['red']) && isset($_POST['green']) && isset($_POST['blue']))
echo color($_POST['red'],$_POST['green'],$_POST['blue']);
?>
<html>
<body>
<form action="" method="post">
	<input type="text" name="red">
	<input type="text" name="green">
	<input type="text" name="blue">
	<input type="submit" value="Click">
</form>
</body>
</html>