I can't seem to apply the $_POST function properly to retrieve the data from a simple HTML form. I'm new to PHP, so I may be overlooking something simple.
I have a form with action directing to the same page, but if the form is filled out, the value of $_POST['input_name'] will have changed, so I can trigger the php function using that condition. Is this the best way to structure this kind of action?
Here's my HTML code (thispage.php is the current/same page):
<form action="thispage.php" method="post">
Name: <input type="text" name="userName" id="userName" />
<input type="submit" />
</form>
Here's my PHP code from the same page:
if("" == trim($_POST['userName'])){
echo $_POST['userName'];
}
Thanks a lot in advance!!
First remove the action from form if your server side code is in the same page. And Use the empty() or isset() functions for checking the value.
For Example:
if(!empty(trim($_POST['userName']))){
echo $_POST['userName'];
}
if(isset(trim($_POST['userName']))){
echo $_POST['userName'];
}
if("" == trim($_POST['userName'])){
echo $_POST['userName'];
}
This is actually checking if the value is empty and echoes it if it is.
You probably want to use !empty($_POST['userName']) to check if it's not empty and then echo it if it is not.
try this:
HTML code
<form action="thispage.php" method="post">
Name: <input type="text" name="userName" id="userName" />
<input type="submit" name="submit" />
</form>
PHP code on the same page:
if(isset($_POST['submit']))
{
if(isset(trim($_POST['userName']))){
echo $_POST['userName'];
}
}
Try this...
if(trim($_POST['userName']) != ' '){
echo $_POST['userName'];
}
you can try it:
if(isset($_POST['userName'])){
$name = $_POST['userName'];
echo $name;
}
Related
I just sent data to a page called diak_o.php with post method but I need to use this data on an another page. How can I send it to two pages or send from the first page to the next?
<form action="diak_o.php" method="post">
<input type="text" name="name"><br>
<input type="submit" value="Bejelentkezés" />
</form>
You could store it in Sessions and access it on multiple pages like this:
Page 1:
<form action="page2.php" method="post">
<input type="text" name="page1text"/>
<input type="submit"/>
</form>
Page 2:
<?php
session_start();
$dataFromPage1 = $_SESSION['page1text'] = $_POST['page1text'];
echo $dataFromPage1;
?>
You can use $_SESSION or just but i think $_POST should still work in the next file too...
when you send that data from this page to second page like diak_o.php in this page you can access it by below code.
in diak_o.php write code like below.
<?PHP
session_start();
echo $_POST['name'];
$_SESSION["name"] = $_POST['name'];
?>
in the other page you can use $_SESSION["name"] by accessing it.
you can also use COOKIE OF PHP.
On this URL there are different methods for passing data from one page to another.
http://www.discussdesk.com/how-to-get-data-from-one-page-to-another-page-in-php.htm
Thanks.
You need to give your button a name attribute, then on diak_o.php you check if the button isset, after that you check if the text input is not empty, else assign a session to the text input
Your Form
<form action="diak_o.php" method="post">
<input type="text" name="name"><br>
<input type="submit" value="Bejelentkezés" name="submit" />
</form>
diak_o.php
<?php
session_start();
if(isset($_POST['submit'])){
if(empty($_POST['name'])){
die("enter name");
}else{
$_SESSION['name']= $_POST['name'];
}
}
?>
anotherpage.php
<?php
session_start();
echo $_SESSION['name']; // will output the value from form.
?>
when ever your wanna use the value on your pages, just use $_SESSION['name'];
I am making account registeration page with php. My problem is taht, if somebody uses username which is already in use, page reloads and all inputs will empty.
I tried this:
<form action="register.php" method="post">
<input type="text" name="username" value="<?php if(isset($_POST['username'])) { echo $_POST['username']; } ?>" />
</br>
In my opinion, the best way is to send the check for a duplicate username via AJAX. Use JavaScript to send the request a second or two after the user is done typing.
If you don't want to use AJAX, store the field values in the session and spit them back out when the page reloads. This is your page:
<?php if(isset($_SESSION['username'])) { echo $_POST['username']; } ?>
Then, in the form submission code:
$_SESSION['username'] = $_POST['username'];
Your code could work if your form-handling code and you form markup are in the same PHP file, but you certainly aren't violating separation of concerns like that, are you? ;)
You have set the method of your form to POST, so you can't use $_GET, instead you have to use $_POST.
<form action="register.php" method="post">
<input type="text" name="username" value="<?php echo htmlspecialchars($_POST['username']); ?>" />
</br>
I want form to post automatically if zip variable is passed from URL.
URL looks like: www.sitename.com/maps/zipsearch.php?zip=90210
Form looks like:
<form method="post">
Zipcode:
<input name="zip" value="<?php echo (isset($_GET["zip"]))? $_GET["zip"]:"";?>" />
<input type="submit" name="subbut" value="Find instructors" />
</form>
So it fills the input box with zip code but I would like it to post automatically to see results again if zip is passed.
Maybe an IF / THEN?
Any help would be appreciated.
You mean to echo the value passed in GET parameter?
<input type="submit" name="subbut" value="<?php echo isset($_GET['zip'])?$_GET['zip']:'Find'; ?>" />
EDIT
Or, if you are asking about submitting the form, then something like this might work I believe:
<input type="submit" name="subbut" value="<?php echo isset($_GET['zip'])?$_GET['zip']:'Find'; ?>" />
<?php if( isset( $_GET['zip'] ) ) { ?>
<script>
document.forms["name_of_the_form_here"].submit();
</script>
<?php } ?>
like this:
<form id="form" action="form.php" method="post">
Zipcode:
<input name="zip" value="<?php echo (isset($_GET["zip"]))? $_GET["zip"]:"";?>" />
<input type="submit" name="subbut" value="Find instructors" />
</form>
<?php if (isset($_GET["zip"])): ?>
<script>document.getElementById('form').submit()</script>
<?php endif; ?>
since passing data via URL means GET method, so i think you have a little misconception with your question.
if you would like to post automatically you dont need to show form.
just put this code in your zipsearch.php
if ($_GET['zip'] != ""){
// do what you want if zip parameter is not null
}else{
// do what you want if zip parameter is null
}
It looks like your form is submitting to itself. (Eg. zipsearch.php displays HTML form. When user submits form, it is posted back to zipsearch.php which displays the search results).
If this is the case, you don't have to post anything, because you are already inside the file that handles the form submission. You could do something like this:
<?php
if (isset ($_POST['zip'])) {
$zip = $_POST['zip']; /* Form was submitted */
} else if (isset ($_GET['zip'])) {
$zip = $_GET['zip']; /* "?zip=" parameter exists */
}
if (isset ($zip)) {
/* Display search results */
} else {
/* Display form */
}
every time i am refreshing the page and i am getting the same value stored in the post array.
i want execution of echo statement only after submit and after refreshing no echo results..
<?php
if(isset($_POST['submit']))
{
$name = $_POST['name'];
echo "User name : <b> $name </b>";
}
?>
<form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="text" name="name"><br>
<input type="submit" name="submit" value="Submit Form"><br>
</form>
From just a form, you won't be able to check if it was a refresh, or a first submit, regardless of using GET or POST method.
To ensure a single message, you need to:
a. redirect the user to somewhere else after you processed the request.
if(isset($_POST['submit'])) {
// process data
header("Location: new-url");
}
And display the message on the other URL.
b. set a cookie / session variable, which tells you the form was already processed.
if(isset($_POST['submit']) && !isset($_SESSION['form_processed'])) {
$_SESSION['form_processed'] = true;
}
This second approach will kill your form until the user closes the browser, so you should do something more complex - like storing another hidden field in the form, and storing that in the session.
If you submit a form and then refresh the resulting page, the browser will re-post the form (usually prompts first). That is why the POST data is always present.
An option would be to store a session variable and have it sent in the form, then check if it matches in the form processing code - to determine if it is a re-post or not.
Within the form:
<input type="hidden" name="time" value="<?php echo $time; ?>" />
In the PHP:
session_start();
if(isset($_POST['submit']))
{
if(isset($_SESSION['time']) && $_SESSION['time'] == $_POST['time'])
{
echo "User name : <b> $name </b>";
}
}
$time = $_SESSION['time'] = time();
Another option is to redirect after processing the post data:
if(isset($_POST['submit']))
{
...
...
header('Location: ' . basename($_SERVER['PHP_SELF']));
exit();
}
You need to maintain a state as to whether $name has already been displayed or not. The easiest way is probably to maintain that state in a browser cookie.
<?php
$nonce = $_COOKIE['nonce'];
$new_nonce = mt_rand();
setcookie('nonce', $new_nonce);
if(isset($_POST['submit']) && $_POST['nonce'] == $nonce)
{
$name = $_POST['name'];
echo "User name : <b> $name </b>";
}
?>
<form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="hidden" name="nonce" value="<?php echo $new_nonce ?>">
<input type="text" name="name"><br>
<input type="submit" name="submit" value="Submit Form"><br>
</form>
Problems
you are polluting the user “session” with stale variable.
this will break if your user opens several windows (or tabs) to the same page. To fix this you would have to change the nonce cookie into an array of nonces, and update it accordingly.
if you want refresh page after submit use
<form method="get"
sure if your form hasn't a lot of data and also need to use $_GET instead of $_POST variable:)
correct way for you, but this logic is not good, need to refactor this script:
<?php
if(isset($_POST['submit']))
{
$name = $_POST['name'];
echo "User name : <b> $name </b>";
unset($_POST['submit']);
}
?>
<form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="text" name="name"><br>
<input type="submit" name="submit" value="Submit Form"><br>
</form>
I am just starting to learn php, how would I initiate a echo statement after a submit button is pushed, or even a anchor tag.
Here is my code so far
form name="myform" method="get" actions="madlib01.php"
Name: <input type="text" name="name" /> <br />
<input type="submit" name="submit" />
form
<?php
$Name = $_GET['name'];
$hello .= "Hello $Name";
echo $hello //I would prefer the echo to happen after the submit button is hit
?>
the correct attribute for your form tag is "action", not "actions"
When the form is submitted, a new request is sent to the server (in your case, using GET).
So to do it all in one page:
form.php:
<form action="form.php" method="GET">
<input type="text" name="name"/>
<input type="submit">
</form>
<?PHP
if (! empty($_GET['name'])){
echo 'Hello, ' . $_GET['name'];
}
?>
You will first need to check if PHP has received your GET parameter using isset or array_key_exists:
if(isset($_GET['name']) && !empty($_GET['name'])) {
$Name = $_GET['name'];
echo "Hello $Name";
}
or:
if(array_key_exists('name', $_GET) && !empty($_GET['name'])) {
$Name = $_GET['name'];
echo "Hello $Name";
} else {
//example: default to something if nothing has been passed
echo "Hello Guest";
}
Also note, if you're submitting to the same page, you can omit the action attribute from your form tag altogether:
<form method="GET">
echo $hello
You've just gained an HTML-injection vulnerability. If someone sends your user to:
http://www.example.com/madlib01.php?name=<script>stealYourCookies()</script>
you've got problems.
Yes, this is a My First PHP Script. That doesn't make security optional. This is a mistake every tutorial makes: teaching bad practice from the start, treating correctness (and security, which is a subset of correctness) as an optional extra.
The result is that most PHP code out there is full of holes. But there's no need for yours to be! Every time you place a pure-text string into a surrounding HTML context, escape it properly:
echo htmlspecialchars($hello);
I tend to define a function with a shorter name than ‘htmlspecialchars’ to do that for me, as I'm lazy.
<?php
function h($text) {
echo(htmlspecialchars($text, ENT_QUOTES));
}
$name= '';
if (isset($_REQUEST['name']))
$name= trim($_REQUEST['name']);
?>
...
<?php if ($name!=='') { ?>
<p> Hello, <?php h($name); ?>! </p>
<?php } ?>
<form method="get" action="madlib01.php">
<p>
<label for="namefield">Name:</label>
<input id="namefield" type="text" name="name" />
</p>
<p>
<input type="submit" />
</p>
</form>
Now if you say your name is Mister <script>, the page will greet you exactly as such, angle brackets and all, instead of trying to run JavaScript. This is the correct output and thus also secure.