Error while if(empty($_POST) === false) being called - php

I have two forms that are being submitted depending on the conditions.
I used
if(empty($_POST) === false)
to save data after an edit. But for the first time I encountered this situation which causes and error.
What do I need to do so that I can accommodate two forms on a page.???

put a hidden field in each of your forms...
<input type="hidden" name="do" value="edit" />
in the other form:
<input type="hidden" name="do" value="new" />
Then check $_POSTfor those specific values:
if (isset($_POST['do'])) {
// a form was posted
if ($_POST['do']=='edit') {
// do sth with form 'edit'
elseif ($_POST['do']=='new') {
// do sth with form 'new'
} // if $_P
} // if isset

I suggest you to use the RESTful approach to this problem. You can check whatever the request method is POST (new) or PUT (edit) and deal with that.
For example if you have two forms, one for edit and one for creating items, you set the method to one of them with:
<form method="PUT" ...>
<form method="POST"...>
and retrieve the method via:
$_SERVER['REQUESTED_METHOD'];
therefore dividing them.

Related

Print_r not working in php [duplicate]

What is the best way of checking whether or not a form has been submitted to determine whether I should pass the form's variables to my validation class?
First I thought maybe:
isset($_POST)
But that will always return true as a superglobal is defined everywhere. I don't want to have to iterate through each element of my form with:
if(isset($_POST['element1']) || isset($_POST['element2']) || isset(...etc
Whilst writing this question I thought of a much more basic solution, add a hidden field to act as a flag that I can check.
Is there a 'cleaner' way to do it than adding my own flag?
For general check if there was a POST action use:
if ($_POST)
EDIT: As stated in the comments, this method won't work for in some cases (e.g. with check boxes and button without a name). You really should use:
if ($_SERVER['REQUEST_METHOD'] == 'POST')
How about
if($_SERVER['REQUEST_METHOD'] == 'POST')
Actually, the submit button already performs this function.
Try in the FORM:
<form method="post">
<input type="submit" name="treasure" value="go!">
</form>
Then in the PHP handler:
if (isset($_POST['treasure'])){
echo "treasure will be set if the form has been submitted (to TRUE, I believe)";
}
Use
if(isset($_POST['submit'])) // name of your submit button
if ($_SERVER['REQUEST_METHOD'] == 'POST').
Try this
<form action="" method="POST" id="formaddtask">
Add Task: <input type="text"name="newtaskname" />
<input type="submit" value="Submit"/>
</form>
//Check if the form is submitted
if($_SERVER['REQUEST_METHOD'] == 'POST' && !empty($_POST['newtaskname'])){
}
On a different note, it is also always a good practice to add a token to your form and verify it to check if the data was not sent from outside. Here are the steps:
Generate a unique token (you can use hash) Ex:
$token = hash (string $algo , string $data [, bool $raw_output = FALSE ] );
Assign this token to a session variable. Ex:
$_SESSION['form_token'] = $token;
Add a hidden input to submit the token. Ex:
input type="hidden" name="token" value="{$token}"
then as part of your validation, check if the submitted token
matches the session var.
Ex: if ( $_POST['token'] === $_SESSION['form_token'] ) ....
I had the same problem - also make sure you add name="" in the input button. Well, that fix worked for me.
if($_SERVER['REQUEST_METHOD'] == 'POST' && !empty($_POST['add'])){
echo "stuff is happening now";
}
<input type="submit" name="add" value="Submit">
You could also use:
is_array($_POST)

changing value of isset

I'm wondering if it's possible to manually change the value of an isset value. That is, to do something like this:
isset($_POST['search_user']) = true;
Why I want to do this: I have two different "submit" forms on one page. When one form is submitted, I want to capture all the values of that form into SESSION variables. However, when the other form is submitted, the SESSION variables are wiped out (since the first form is not, technically, submitted anymore).
My idea was that, if the second form is submitted, then automatically set the value of the first form to true
If I understand your question correctly, if a second form is submitted, why not just destroy the current session and start new sessions using the variables posted from the new form?
http://php.net/manual/en/function.session-destroy.php
session_destroy();
...Or, you can set another session variable if the second form is submitted:
if (isset($_POST['search_user'])) {
$_SESSION['search_user'] = "true";
}
if ($_SESSION['search_user'] == "true") {
// Second form was submitted
}
You can try to define a name and a value for each submit button, so you retrieve this in the PHP file and do what you want, according you need. For instance:
HTML to the first form:
<form name="form1" action="page2.php" method="post">
<input type="submit" value="1" name="button01">
</form>
HTML to the second form:
<form name="form2" action="page2.php" method="post">
<input type="submit" value="1" name="button02">
</form>
Then you can detect the form thas was submited doing this in page2.php:
if($_POST['button01'] == "1")
{
// Do what you need based on form1 submit
}
elseif($_POST['button02'] == "1")
{
// Do what you need based on form2 submit
}
Try this and then leave some comment telling if it helps you.

PHP avoiding a long POST

This is more of a technique question rather than maybe code. I am having a php form with many fields (items to select). Naturally some of the items might be selected and some not. How do I know which ones are selected when i post the data from page 1 to page 2? I thought of testing each one if empty or not, but there are just too many fields and it doesn't feel at all efficient to use or code.
Thanks,
UPDATE EDIT:
I've tried the following and maybe it will get me somewhere before I carry on testing the repliers solutions...
<html>
<body>
<form name="test" id="name" action="testprocess.php" method="POST">
<input type="text" name="choices[shirt]">
<input type="text" name="choices[pants]">
<input type="text" name="choices[tie]">
<input type="text" name="choices[socks]">
<input type="submit" value="submit data" />
</form>
</body>
</html>
and then second page:
<?php
$names = $_POST['choices'];
echo "Names are: <br>";
print_r($names);
?>
This gives out the following:
Names are: Array ( [shirt] => sdjalskdjlk [pants] => lkjlkjlk [tie]
=> jlk [socks] => lkjlkjl )
Now what I am going to try to do is iterate over the array, and since the values in my case are numbers, I will just check which of the fields are > 0 given the default is 0. I hope this works...if not then I will let you know :)
I think what you're looking for is this:
<form action="submit.php" method="POST">
<input type="checkbox" name="checkboxes[]" value="this" /> This
<input type="checkbox" name="checkboxes[]" value="might" /> might
<input type="checkbox" name="checkboxes[]" value="work" /> work
<input type="submit" />
</form>
And then in submit.php, you simply write:
<?php
foreach($_POST['checkboxes'] as $value) {
echo "{$value} was checked!";
}
?>
The square brackets in the name of the checkbox elements tell PHP to put all elements with this name into the same array, in this case $_POST['checkboxes'], though you could call the checkboxes anything you like, of course.
You should post your code so we would better understand what you want to do.
But from what I understood you are making a form with check boxes. If you want to see if the check boxes are selected, you can go like this:
if(!$_POST['checkbox1'] && !$_POST['checkbox2'] && !$_POST['checkbox3'])
This looks if all the three check boxes are empty.
Just an idea:
Create a hidden input field within your form with no value. Whenever any of the forms fields is filled/selected, you add the name attribute of that field in this hidden field (Field names are saved with a comma separator).
On doing a POST, you can read this variable and only those fields present in this have been selected/filled in the form.
Hope this helps.
Try this.....
<?php
function checkvalue($val) {
if($val != "") return true;
else return false;
}
if(isset($_POST['submit'])) {
$values = array_filter(($_POST), "checkvalue");
$set_values = array_keys($values);
}
?>
In this manner you can get all the values that has been set in an array..
I'm not exactly sure to understand your intention. I assume that you have multiple form fields you'd like to part into different Web pages (e.g. a typical survey form).
If this is the case use sessions to store the different data of your forms until the "final submit button" (e.g. on the last page) has been pressed.
How do I know which ones are selected when i post the data from page 1 to page 2?
is a different question from how to avoid a large POST to PHP.
Assuming this is a table of data...
Just update everything regardless (if you've got the primary / unique keys set correctly)
Use Ajax to update individual rows as they are changed at the front end
Use Javascript to set a flag within each row when the data in that row is modified
Or store a representation of the existing data for each row as a hidden field for the row, on submission e.g.
print "<form....><table>\n";
foreach ($row as $id=>$r) {
print "<tr><td><input type='hidden' name='prev[$id]' value='"
. md5(serialize($r)) . "'>...
}
...at the receiving end...
foreach ($_POST['prev'] as $id=>$prev) {
$sent_back=array( /* the field values in the row */ );
if (md5(serialize($sent_back)) != $prev) {
// data has changed
update_record($id, $sent_back);
}
}

Form to form with PHP

I am trying to create a multi steps form where user will fill the form on page1.php and by submitting can go to page2.php to the next 'form'. What would be the easiest way?
Here is my code:
<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
?>
<form id="pdf" method="post">
New project name:<input type="text" name="pr_name" placeholder="new project name..."><br/>
New project end date:<input id="datepicker" type="text" name="pr_end" placeholder="yyyy-mm-dd..."><br/>
<textarea class="ckeditor" name="pagecontent" id="pagecontent"></textarea>
<?php
if ($_POST["pr_name"]!="")
{
// data collection
$prname = $_POST["pr_name"];
$prend = $_POST["pr_end"];
$prmenu = "pdf";
$prcontent = $_POST["pagecontent"];
//SQL INSERT with error checking for test
$stmt = $pdo->prepare("INSERT INTO projects (prname, enddate, sel, content) VALUES(?,?,?,?)");
if (!$stmt) echo "\nPDO::errorInfo():\n";
$stmt->execute(array($prname,$prend, $prmenu, $prcontent));
}
// somehow I need to check this
if (data inserted ok) {
header("Location: pr-pdf2.php");
}
}
$sbmt_caption = "continue ->";
?>
<input id="submitButton" name="submit_name" type="submit" value="<?php echo $sbmt_caption?>"/>
</form>
I have changed following Marc advise, but I don't know how to check if the SQL INSERT was OK.
Could give someone give me some hint on this?
thanks in advance
Andras
the solution as I could not answer to my question (timed out:):
Here is my final code, can be a little bit simple but it works and there are possibilities to check and upgrade later. Thanks to everyone especially Marc.
<form id="pdf" method="post" action="pr-pdf1.php">
New project name:<input type="text" name="pr_name" placeholder="new project name..."><br/>
Email subject:<input type="text" name="pr_subject" placeholder="must be filled..."><br/>
New project end date:<input id="datepicker" type="text" name="pr_end" placeholder="yyyy-mm-dd..."><br/>
<textarea class="ckeditor" name="pagecontent" id="pagecontent"></textarea>
<?php
include_once "ckeditor/ckeditor.php";
$CKEditor = new CKEditor();
$CKEditor->basePath = 'ckeditor/';
// Set global configuration (will be used by all instances of CKEditor).
$CKEditor->config['width'] = 600;
// Change default textarea attributes
$CKEditor->textareaAttributes = array(“cols” => 80, “rows” => 10);
$CKEditor->replace("pagecontent");
if ($_SERVER['REQUEST_METHOD'] == 'POST')
{
// data collection
$prname = $_POST["pr_name"];
$prsubject = $_POST["pr_subject"];
$prend = $_POST["pr_end"];
$prmenu = "pdf";
$prcontent = $_POST["pagecontent"];
//SQL INSERT with error checking for test
$stmt = $pdo->prepare("INSERT INTO projects (prname, subject, enddate, sel, content) VALUES(?,?,?,?,?)");
// error checking
if (!$stmt) echo "\nPDO::errorInfo():\n";
// SQL command check...
if ($stmt->execute(array($prname, $prsubject, $prend, $prmenu, $prcontent))){
header("Location: pr-pdf2.php");
}
else{
echo"Try again because of the SQL INSERT failing...";
};
}
$sbmt_caption = "continue ->";
?>
<input id="submitButton" name="submit_name" type="submit" value="<?php echo $sbmt_caption?>"/>
</form>
Add the attribute action with the url you'd like to go to. In this case it'd be
<form id="pdf" method="post" action="page2.php">
EDIT: i missed you saying this method doesn't work. What part of it doesn't work?
You should keep the action to the same script, so the POST action is still performed and then redirect with header("Location: page2.php"); when the processing is done.
A basic structure like this will do it:
form1.php:
<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
... process form data here ...
if (form data ok) {
... insert into database ...
}
if (data inserted ok) {
header("Location: form2.php");
}
}
?>
... display page #1 form here ...
And then the same basic structure for each subsequent page. Always submit the form back to the page it came from, and redirect to the next page if everything's ok.
You're probably better off separating the php code from the form. Put the php code in a file called submit.php, set the form action equal to submit.php, and then add the line header('Location: whateverurl.com'); to your code.
The easiest way is to post it to form2.php by giving the form the attribute action="page2.php". But there's a risk in that. It means that form2 must parse the posted data of form1. Also, if the data is wrong (verification) form1 must be shown instead of form2. This will make your code over complicated and creates dependencies between the two forms.
So the better solution (and quite easy as well) is to implement the post-redirect-get pattern.
You post to form1, verify all data and store it. If the data is ok, you redirect to form2. If the data is wrong, you just show form1 again.
Redirecting is done by a header:
// Officially you'll need a full url in this header, but relative paths
// are accepted by all browsers.
header('Location: form2.php');
Save already posted fields in hidden input fields, but don't forget to validate them every time user submits another step of the form as the user may change hidden inputs in source code.
<input type="hidden" name"some_name" value="submitted_value"/>
There are several ways handling the submitted data while jumping between steps.
You will find your reasons for /against writing data to session, database, whatever... after each step or not.
I did following approach:
The form includes always a complete set of input elements, but on page #1 the step-2-elements are hidden ... and other way round.
I built a 6-step-wizard this way. One large template, some JS /Ajax for validating input, additional hidden inputs that hold current step-ID and PHP deciding, which fields to show or hide.
The benfit in my opinion: Data can easily be saved completely, as soon as input is alright and complete. No garbage handling, if users abort after step 1.
I would store it all in a session array (or sub array)
a really rough example where I'm saving all the form names to an array (to be checked later of course):
<?
foreach($_POST as $k => $v){
$session['register'][$k]=$v;}
?>

Can one form have multiple actions?

I am wanting to submit a form to different places based on selections made in the form. I had originally been planning to to send all to a central file/location and have it determine where to go next. However, I would like to do without this extra step if I could.
If the user wants to create/edit/delete elements go to page 1.
If the user wants to group/attach elements go to page 3.
I am trying to write a form builder. You can create/edit/delete forms, questions, and answers. I have everything for creating, editing, and deleting done. Those functions are performed without leaving the page, but now I am looking to assign answers to specific questions. The questions page and the answers page are separate. I am wanting to select a group of answers and submit an array of answer Ids (selected check boxes) to the question page where those Ids will then be assigned to a question. So basically the create, edit, and delete functions are on without leaving the page, but the assign function would be performed on a different page.
if(empty($delRowID) || empty(updateRowID) || empty($groupRows)) {
qInsert();
}else{
if(!empty($delRowID)) qDelete($delRowID);
if(!empty(updateRowID)) qUpdate($updateRowID);
if(!empty($groupRows)) {
submit $groupRows to Question.php;
}
}
No, a form has only one action.
But you have options:
Javascript
However, you may change the action attribute with javascript:
<input type="submit" value="Edit" onclick="editform();return true;">
<input type="submit" value="Delete" onclick="deleteform();return true;">
together with a little javascript:
function editform() {
document.myform.action = '/edit';
}
function deleteform() {
document.myform.action = '/delete';
}
See also
How to set form action through JavaScript?
Different form ACTION depending on button pressed
jquery, changing form action
Multiple forms
If javascript is not an option for you, you may consider multiple forms in your page.
Multiple forms = multiple actions
No problems with javascript disabled clients, and standards compliant.
Multiple submit buttons - server side
Or you may handle the distinction of editing or deleting on the server side. No javascript needed.
Add multiple submit buttons to your form and give them the same name but a different value:
<input type="submit" name="btSubmit" value="Edit">
<input type="submit" name="btSubmit" value="Delete">
You then can retrieve the value of the button which has been clicked. In php, the following should do the job:
$_POST['btSubmit']
See http://www.chami.com/tips/internet/042599I.html for an example with classic asp.
It is possible using JavaScript, but it's not recommended because some people turn JS off by default because of trojans and noisy behavior of some sites. It is considered polite to have your site working both with JS enabled and disabled.
Actually you don't need many form actions because every operation can be done using branching in the single form handler script.
Here is the very simple CRUD application example, performing displaying, editing, adding - all in one body and utilizing templates:
index.php
<?
mysql_connect();
mysql_select_db("new");
$table = "test";
if($_SERVER['REQUEST_METHOD']=='POST') { //form handler part:
$name = mysql_real_escape_string($_POST['name']);
if ($id = intval($_POST['id'])) {
$query="UPDATE $table SET name='$name' WHERE id=$id";
} else {
$query="INSERT INTO $table SET name='$name'";
}
mysql_query($query) or trigger_error(mysql_error()." in ".$query);
header("Location: http://".$_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF']);
exit;
}
if (!isset($_GET['id'])) { //listing part:
$LIST=array();
$query="SELECT * FROM $table";
$res=mysql_query($query);
while($row=mysql_fetch_assoc($res)) $LIST[]=$row;
include 'list.php';
} else { // form displaying part:
if ($id=intval($_GET['id'])) {
$query="SELECT * FROM $table WHERE id=$id";
$res=mysql_query($query);
$row=mysql_fetch_assoc($res);
foreach ($row as $k => $v) $row[$k]=htmlspecialchars($v);
} else {
$row['name']='';
$row['id']=0;
}
include 'form.php';
}
?>
form.php
<form method="POST">
<input type="text" name="name" value="<?=$row['name']?>"><br>
<input type="hidden" name="id" value="<?=$row['id']?>">
<input type="submit"><br>
Return to the list
</form>
list.php
Add item
<? foreach ($LIST as $row): ?>
<li><?=$row['name']?>
<? endforeach ?>
Just send them to a central location and use logic to send them somewhere else depending on what they selected.
eg:
<?php
switch($_POST['choice']) {
case 'edit':
$page = 'edit.php';
break;
case 'group':
$page = 'group.php';
break;
}
header("Location: " . $page);
(obviously needs some input filtering and default values)
EDIT: as pointed out by Col. Shrapnel below, using header() for this is pretty pointless as it'll then wipe out your $_POST array - use include() instead, but be careful to only allow your own files and never let the user name the file which will be included (eg using a form field value to pick the included file).
No, you can't have multiple actions just in the html, but you can use javascript to switch up the action depending on what button is hit.
I would do something like this (in pseudo-mootools)
<form action='default.php'>
... form elements ...
<button onclick='editButtonClick()' value='edit'/>
<button onclick='deleteButtonClick()' value='delete'/>
</form>
function editButtonClick() {
$('form').action = 'editaction.php';
$('form').submit();
}
function deleteButtonClick) {
$('form').action = 'deleteaction.php';
$('form').submit();
}
No, it can't (at least not without depending on JavaScript).
Submit to one URI, and have a dispatch routine pass the data off to different functions depending on which radio button (or whatever) is selected.
If I was looking at doing this I would pass a vaule of what you want doing by POST.
Then check that value against a set of functions and each function will do a different thing based on it selection
<input type="submit" value="Add" onclick="submitForm(this,'add')" />
<input type="submit" value="Update" onclick="submitForm(this,'update')" />
<input type="submit" value="Delete" onclick="submitForm(this,'delete')" />
var submitForm = function(context,uri)
{
form = contenxt.parent; //Go back to the form
form.action = uri; // Set the action
form.submit(); //Submit the form;
}
Java script is the best way to handle this, there's not really much alternative unless you create 3 sole forms.
Post your form to a central formhandler script. On that page just use simple logic (using php in this instance) to redirect the user to the specific page you want
on Submit page you can call CURL and give all Get or post variables to that url.

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