用php在会话中存储表单数据

Question

I'm testing a really basic PHP form, where the form data is saved in a session. Later, i want that session data to be the default value of the form:

<strong>Test Form</strong>
<form action="" method"post">
<input type="text" name="var" value=<?php $name ?>
<input type="submit" name="Submit" value="Submit!" />
</form>

<?php 

 // starting the session
 session_start();


 if (isset($_POST['Submit'])) { 
 $_SESSION['var'] = $_POST['var'];
 $name = $_SESSION['var'];
 }

 echo $name;
?> 

So, for example if i input "MyName" it should echo "MyName" and in the form there should be the value "MyName". The problem with the actual code is that it gives an E_NOTICE : type 8 -- Undefined variable: name -- at line 18 error. I think that the variable is not being stored, can someone help me out on this?

Answer 1

Spotted a few things:

1. I'd put the session_start(); at the top of the page before outputting anything.
2. Your method was incorrectly written it needs a '=' when specifying the method - thats the main reason why nothing was being stored, the form wasn't submitting properly.
3. Same with how you've put in the value on the name input - it has no '=' and you don't close the input tag properly - I've left it blank and added a placeholder - you can change it to what you need.

Heres how I'd do it:

<?php session_start(); ?>
<strong>Test Form</strong>
<form action="" method="post">
<input type="text" name="var" value="" placeholder="enter name">
<input type="submit" name="Submit" value="Submit!" />
</form>
<?php
if (isset($_POST['Submit'])) {
  $_SESSION['var'] = $_POST['var'];
}
// Store the session in a variable after the submit - otherwise it will be forgotten on refresh
$name = $_SESSION['var'];
// check if session exists
if(isset($name)) {
  echo $name;
}
else {
  echo 'no name entered...';
}
?>

You can edit the above to hide the form if a name has been submitted etc. Use session_destroy(); to reset the stored session.

Cheers

Answer 2

The first error I notice is this piece of code:

<form action="" method"post">

Where method does not contain the symbol "=" which causes the loss of the parameter post. Furthermore, the "session_start ()" function must be placed before any other code. The code derives from this is as follows:

<?php
// starting the session
session_start();

if (isset($_POST['Submit'])) { 
    $_SESSION['var'] = $_POST['var'];
    $name = $_SESSION['var'];
} else {
    $name = null;
}
?>

<strong>Test Form</strong>
<form action="" method="post" enctype="multipart/form-data">
    <input type="text" name="var" value="<?= ($name != null) ? $name : ''; ?>">
    <input type="submit" name="Submit" value="Submit!" />
</form>