<?php
$number_to_guess = 42;
$num_tries = (isset($_POST['num_tries']))? $num_tries+1:1;
if(!isset($_POST['guess']))
$message = "Welcome to the guessing machine!";
elseif(!is_numeric($_POST['guess']))
$message = "Not a num!";
else if($_POST['guess'] == $number_to_guess)
$message = "Well Done!";
else if($_POST['guess'] > $number_to_guess)
$message = $_POST['guess']." is too big, Try a smaller one!";
else if($_POST['guess'] < $number_to_guess)
$message = $_POST['guess']." is too small, Try a bigger one!";
else
$message = "I am terribly confused!";
echo $_SERVER['PHP_SELF'];
?>
<!DOCTYPE html>
<html>
<head>
<title>A HTML/PHP that calls itself!</title>
</head>
<body>
<h1>
<?php
echo "Guessing Result:<br/>\"".$message."\"";
?>
</h1>
<p><strong>Guess number:</strong>
<?php
echo $num_tries;
?>
</p>
<form method="post" action="
<?php
echo $_SERVER['PHP_SELF'];
?>
">
<p><label for="guess">Type your guess here:</label><br/>
<input type="text" id="guess" name="guess"/></p>
<input type="hidden" name="num_tries" value="
<?php
echo $num_tries;
?>" /></p>
<button type="submit" name="submit" value="send">Guess it!</button>
</form>
</body>
</html>
把isset改成empty試一下。
