Question

我在php中创建了一个简单的程序。我让用户输入一个字符串然后打印出字符串的反向。我的问题是如何在按下提交按钮后隐藏表单？我写的代码在

下面

<?php
//TASK 16 ENTER A STRING AND REVERSE IT

$str = $_POST['usersString'];

$len = strlen($str);

for($i=($len-1); $i>=0; $i--){
    echo $str[$i];
}




?>

<form action="task16.php" method="POST">
Enter a string to reverse! <input type="text" name="usersString" />
<input type="submit" value="enter" />
</form>

Answer 1

<?php
//TASK 16 ENTER A STRING AND REVERSE IT

if( isset( $_POST['usersString'] ) && !empty( $_POST['usersString'] ) )
{
    $str = $_POST['usersString'];
    $len = strlen($str);
    for($i=($len-1); $i>=0; $i--){
        echo $str[$i];
    }
} else {
?>
<form action="task16.php" method="POST">
Enter a string to reverse! <input type="text" name="usersString" />
<input type="submit" value="enter" />
</form>
<?php
}
?>

Answer 2

<?php
//TASK 16 ENTER A STRING AND REVERSE IT

$str = $_POST['usersString'];

$len = strlen($str);

for($i=($len-1); $i>=0; $i--){
    echo $str[$i];
}


if (empty($_POST)) {

?>

<form action="task16.php" method="POST">
Enter a string to reverse! <input type="text" name="usersString" />
<input type="submit" value="enter" />
</form>
<?php
}
?>

Answer 3

将此页面设为 task.php

<?php
//TASK 16 ENTER A STRING AND REVERSE IT
$str = $_POST['usersString'];
$len = strlen($str);
for($i=($len-1); $i>=0; $i--){
    echo $str[$i];}
?>

将其设为html表单页面名称，无论您想要什么

<html>
<body>
    <form action="task.php" method="POST">
    Enter a string to reverse! <input type="text" name="usersString" />
    <input type="submit" value="enter" />
    </form>
</body>
</html>

现在，当您的用户在表单页面上输入值时，操作将在task.php上进行，它将仅显示您想要的内容而不显示任何其他内容。

Answer 4

<?php
if (isset($_POST["submit"]) && isset($_POST['usersString'])){

//TASK 16 ENTER A STRING AND REVERSE IT

$str = $_POST['usersString'];

$len = strlen($str);

for($i=($len-1); $i>=0; $i--){
    echo $str[$i];
}

} elseif (!isset($_POST['usersString'])){
?>

<form action="task16.php" method="POST">
Enter a string to reverse! <input type="text" name="usersString" />
<input type="submit" value="enter" />
</form>

<?php
}
?>

如何在按下提交按钮后隐藏表单

4 个答案: