我的代码应该提供两个随机数，让用户输入他们的产品（乘法）。
如果输入错误的答案，它会告诉您再次猜测，但保留相同的随机数，直到您正确回答。正确回答，并从一对新数字开始。
即使输入了错误的数字，下面的代码也会更改两个随机数的值。我想保持值相同，直到输入正确的答案。
<?php
$num1=rand(1, 9);
$num2=rand(1, 9);
$num3=$num1*$num2;
$num_to_guess = $num3;
echo $num1."x".$num2."= <br>";
if ($_POST['guess'] == $num_to_guess)
{ // matches!
$message = "Well done!";
}
elseif ($_POST['guess'] > $num_to_guess)
{
$message = $_POST['guess']." is too big! Try a smaller number.";
}
elseif ($_POST['guess'] < $num_to_guess)
{
$message = $_POST['guess']." is too small! Try a larger number.";
}
else
{ // some other condition
$message = "I am terribly confused.";
}
?>
<!DOCTYPE html>
<html>
<body>
<h2><?php echo $message; ?></h2>
<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="hidden" name="answer" value="<?php echo $answer;?>">
<input type="hidden" name="expression" value="<?php echo $expression;?>">
What is the value of the following multiplication expression: <br><br>
<?php echo $expression; ?> <input type="text" name="guess"><br>
<input type="submit" value="Check">
</form>
</body>
</html>
答案 0 :(得分：0)
为了保持相同的数字，你必须将它们存储在页面上，然后在使用php提交表单时检查它们。如果表单从未提交，您还必须设置随机数。在您的情况下，您总是更改num1和num2。我试图尽可能多地保留原始代码，但仍需要一些工作来简化它。
您可以在下面的代码中看到评论。
此外，如果您打算在生产环境中使用此功能，则需要验证从表单传入的值，以便恶意用户不会利用您的代码。 ：）
<?php
// Setting $num1 and $num2 to what was posted previously and performing the math on it.
$num1 = $_POST['num1'];
$num2 = $_POST['num2'];
$num_to_guess = $num1*$num2;
// Check for the correct answer
if ($_POST && $_POST['guess'] == $num_to_guess)
{
// matches!
$message = "Well done!";
$num1=rand(1, 9);
$num2=rand(1, 9);
}
// Give the user a hint that the number is too big
elseif ($_POST['guess'] > $num_to_guess)
{
$message = $_POST['guess']." is too big! Try a smaller number.";
}
// Give the user a hint that the number is too small
elseif ($_POST['guess'] < $num_to_guess)
{
$message = $_POST['guess']." is too small! Try a larger number.";
}
// If the form wasn't submitted i.e. no POST or something else went wrong
else
{
// Only display this message if the form was submitted, but there were no expected values
if ($_POST)
{
// some other condition and only if something was posted
$message = "I am terribly confused.";
}
// set num1 and num2 if there wasn't anything posted
$num1=rand(1, 9);
$num2=rand(1, 9);
}
// Show the problem
echo $num1."x".$num2."= <br>";
?>
<!DOCTYPE html>
<html>
<body>
<h2><?php echo $message; ?></h2>
<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="hidden" name="num1" value="<?= $num1 ?>" />
<input type="hidden" name="num2" value="<?= $num2 ?>" />
<input type="hidden" name="answer" value="<?php echo $num3;?>">
<input type="hidden" name="expression" value="<?php echo $expression;?>">
What is the value of the following multiplication expression: <br><br>
<input type="text" name="guess"><br>
<input type="submit" value="Check">
</form>
</body>
</html>
答案 1 :(得分：0)
当您第一次加载页面时，您有（即）“2 * 3”作为问题。 $_POST未定义，因此if ($_POST['guess']...将生成未定义索引警告。然后你回复$message，但你定义$message的位置？ $_POST['guess']未定义，因此评估为0，$num_to_guess为6（= 2 * 3），因此$message设置为“太小！尝试更大的数字。”，甚至如果用户没有输入任何内容。隐藏的answer设置为$answer，但未定义此变量，因此将其设置为空（或注意“通知：未定义的变量：回答”，如果激活错误报告）。 expression输入和echo $expression的相同问题。
尝试这样的事情：
$newQuestion = True; // This variable to check if a new multiplication is required
$message = '';
/* $_POST['guess'] check only if form is submitted: */
if( isset( $_POST['guess'] ) )
{
/* Comparison with answer, not with new result: */
if( $_POST['guess'] == $_POST['answer'] )
{
$message = "Well done!";
}
else
{
/* If result if wrong, no new question needed, so we propose same question: */
$newQuestion = False;
$answer = $_POST['answer'];
$expression = $_POST['expression'];
if( $_POST['guess'] > $_POST['answer'] )
{
$message = "{$_POST['guess']} is too big! Try a smaller number.";
}
else
{
$message = "{$_POST['guess']} is too small! Try a larger number.";
}
}
}
/* New question is generated only on first page load or if previous answer is ok: */
if( $newQuestion )
{
$num1 = rand( 1, 9 );
$num2 = rand( 1, 9 );
$answer = $num1*$num2;
$expression = "$num1 x $num2";
if( $message ) $message .= "<br>Try a new one:";
else $message = "Try:";
}
?>
<!DOCTYPE html>
(... Your HTML Here ...)
答案 2 :(得分：0)
这也可能很有趣。这是一个会话。让您暂时存储一些东西。这有点脏。但要学习有趣。 http://www.w3schools.com/php/php_sessions.asp
<?php
session_start(); // Starts the Session.
function Save() { // Function to save $num1 and $num2 in a Session.
$_SESSION['num1'] = rand(1, 9);
$_SESSION['num2'] = rand(1, 9);
$_SESSION['num_to_guess'] = $_SESSION['num1']*$_SESSION['num2'];;
$Som = 'Guess the number: ' . $_SESSION['num1'] .'*' .$_SESSION['num2'];
}
// If there is no session set
if (!isset($_SESSION['num_to_guess'])) {
Save();
$message = "";
}
if (isset($_POST['guess'])) {
// Check for the correct answer
if ($_POST['guess'] == $_SESSION['num_to_guess']) {
$message = "Well done!";
session_destroy(); // Destroys the Session.
Save(); // Set new Sessions.
}
// Give the user a hint that the number is too big
elseif ($_POST['guess'] > $_SESSION['num_to_guess']) {
$message = $_POST['guess']." is too big! Try a smaller number.";
$Som = 'Guess the number: ' . $_SESSION['num1'] .'*' .$_SESSION['num2'];
}
// Give the user a hint that the number is too small
elseif ($_POST['guess'] < $_SESSION['num_to_guess']) {
$message = $_POST['guess']." is too small! Try a larger number.";
$Som = 'Guess the number: ' . $_SESSION['num1'] .'*' .$_SESSION['num2'];
}
// some other condition
else {
$message = "I am terribly confused.";
}
}
?>
<html>
<body>
<h2><?php echo $Som . '<br>'; ?>
<?php echo $message; ?></h2>
<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="text" name="guess"><br>
<input type="submit" value="Check">
</form>
</body>
</html>