php form result loop - php

I'm trying to make a BASIC roulette script.
Is there anyway to get the submitted results of a form using PHP? In fact I know theres a way, but i can't find out how to do it.
So say if my form had several fields I want the result to loop through and show me which fields were filled and the numbers in each.
UPDATE: And say the form has about 40 fields, would I have to name each one in the loop? Any easier way?

$_GET or $_POST depending on the form method.

if(isset($_REQUEST['formInputName'])){
echo $_REQUEST['formInputName'];
}
$_REQUEST looks for GET, POST, and COOKIE.
You can also use $_GET to get a variable from the url (asdf.php?var=2).

If your form looks like this:
<form method="post" action="result.php">
<input type="text" name="foo">
</form>
In result.php you can use the global variable $_POST and loop through it if you want:
foreach($_POST as $name => $value) {
echo $name . ' = ' . $value;
}
If your form has 40 fields, you still need to name them all, but you can automate the process of naming and retrieving them with a loop. For example, if you wanted to create a sum with the value of all the fields, you could name them number1, number2, etc and do:
$sum = 0;
for($i = 1; $i <= 40; $i++)
$sum += $_POST['number' . $i];

You need to define the name of each field using name="something" in the input element, and than in the PHP you're getting it using $_POST['something'] in case you sent the form as method="post" or $_GET['something'] in case of get method
You can see what's sent using var_dump() or print_r(), just write something like that:
echo '<pre>';
print_r($_POST);
Or you can go all over the array using foreach statement:
<?php
foreach($_POST AS $key=>$val)
{
echo $key.': '.$val."<br />\n";
}
?>

Related

Store _POST into variable to use with Page Data [duplicate]

I'm making a php script that stores 3 arrays: $images, $urls, $titles based on the input data of the form within the php file.
I want to print the values of these arrays in the first part of the page and then to pre-fill the form's input fields with the value of the arrays. Also when a user modifies an input field and clicks on "Save" the page should reload with the modfied version.
My problem is that on each call of the php file in a browser the value of the variables gets deleted. Is there a way to store the values of the array so that the form always gets pre-filled with the last saved values?
<?php
//save the arrays with the form data
$images = array($_POST["i0"],$_POST["i1"],$_POST["i2"],$_POST["i3"]);
$urls = array($_POST["u0"],$_POST["u1"],$_POST["u2"],$_POST["u3"]);
$titles = array($_POST["t0"],$_POST["t1"],$_POST["t2"],$_POST["t3"]);
//print the arrays
print_r($images);
print_r($urls);
print_r($titles);
//create the form and populate it
echo "<p><form method='post' action='".$_SERVER['PHP_SELF']."';";
$x = 0;
while ($x <= 3) {
echo"<div>
<input name='i".$x."' type='text' value='".$images[$x]."'>
<input name='u".$x."' type='text' value='".$urls[$x]."'>
<input name='t".$x."' type='text' value='".$titles[$x]."'>";
$x++;
}
?>
<br>
<input type="submit" name="sumbit" value="Save"><br>
</form>
Store the variables in a PHP session.
session_start();
$_SESSION['images'] = $images;
Then on next (or any other) page, you can retrieve the values as:
session_start();
$images = $_SESSION['images'];
Changing the scope of the variables to a larger scope, might do the trick. Also, check if you have a post request before updating the values.
<?php
if(sizeof($_POST) >0)
{
//UPDATE VALUES
}
?>
If you want a permanent storage of state, between different pages, you should use sessions, by putting session_start(); in the start of your script. After this, every variable $_SESSION[$x] will be persisted, and will be available to your scripts.
However, in this particular case, answering your question: "Is there a way to store the values of the array so that the form always gets pre-filled with the last saved values?", it is easier to just use the $_POST variable if it exists already:
<?php
if(!$_POST){
$_POST = array();
foreach(array("i0","i1","i2","i3") as $i) $_POST[$i]="";
foreach(array("u0","u1","u2","u3") as $i) $_POST[$i]="";
foreach(array("t0","t1","t2","t3") as $i) $_POST[$i]="";
}
foreach($_POST as $k=>$v) filter_input(INPUT_POST,$k,FILTER_SANITIZE_SPECIAL_CHARS);
//save the arrays with the form data
$images = array($_POST["i0"], $_POST["i1"], $_POST["i2"], $_POST["i3"]);
$urls = array($_POST["u0"], $_POST["u1"], $_POST["u2"], $_POST["u3"]);
$titles = array($_POST["t0"], $_POST["t1"], $_POST["t2"], $_POST["t3"]);
//print the arrays
print_r($images);
print_r($urls);
print_r($titles);
//create the form and populate it
echo "<p><form method='post' action='".$_SERVER['PHP_SELF']."';";
$x = 0;
while ($x <= 3) {
echo"<div>
<input name='i".$x."' type='text' value='".$images[$x]."'>
<input name='u".$x."' type='text' value='".$urls[$x]."'>
<input name='t".$x."' type='text' value='".$titles[$x]."'>";
$x++;
}
?>
<br>
<input type="submit" name="sumbit" value="Save"><br>
</form>
Note: this line foreach($_POST as $k=>$v) filter_input(INPUT_POST,$k,FILTER_SANITIZE_SPECIAL_CHARS);
should be enough to protect you from basic XSS attacks.
Note also that in general, it is best to follow the pattern of reloading pages with GET after POST, which makes you less susceptible to form resubmitions, in which case using sessions for storage is the better solution.
What brought me here was somewhat different kind of beast. I had problem with subsequent post request from AXIS IP camera and needed to preserve last file name across requests. In case that someone stumble here looking for some way to cache variables and SESSION is not an option maybe should look at Alternative PHP Cache:
Note: Unlike many other mechanisms in PHP, variables stored using
apc_store() will persist between requests (until the value is removed
from the cache).
http://php.net/manual/en/book.apc.php
Use sessions: http://php.net/manual/en/function.session-start.php
You can use sessions to store values and write rules to refill form fields after validations on data submit. Also function isset() is very helpful to avoid "not defined" errors.
The solution you are looking for is the session. Use $_SESSION to store value of Your variables. For example, at the end of script:
$_SESSION['images'] = $images;
and in form's input:
<input name='i".$x."' type='text' value='".(isset($_SESSION['images']) ?
$_SESSION['images'] : '')."'>

How can I handle a $_POST variable identifier as a variable?

Re-writing the question here so it's (hopefully) easier to understand.
I have a piece php that received a $_POST from a form. Each time a $_POST is completed, only one set of data is sent. It could be $_$POST['boat'] or $_POST['car'] or $_POST['dog'] etc. I do not know what the post will contain upon receiving it. If it is $_POST['dog'] then the value of the post will go into the $database.dog table. If it is $_POST['car'] then the value of the post will head into the $database.car table, and so on.
Once a post is made, how can I identify whether the post was called 'car' or 'dog' or 'boat' or anything else ?
There's a lot of ways to do this. Simply with ifs:
if(isset($_POST['car'])) {
// do car stuff
}
if(isset($_POST['boat'])) {
// do boat stuff
}
//etc...
Or a switch:
switch(true) {
case(isset($_POST['car'])):
// do car stuff
break;
case(isset($_POST['boat'])):
// do boat stuff
break;
//etc...
}
To avoid the ifs or switch you can use a hidden input:
<input type="hidden" name="form" value="car">
Then use $_POST['form'] to dynamically build your queries etc...
If car or boat etc... is the only key under $_POST or if it is always the first key then:
$form = key($_POST);
You can get the key/index and value and print that info if you are unsure what the keys or values will be that are coming from your form POST.
function getKeyValuePairs() {
$stmt = null;
if(isset($_POST)){
foreach($_POST as $key => $value) {
$stmt .= $key." => ".$value."<br>";
}
print_r($stmt);
}
Because $_POST is global no need to push variable into function.
HTML: run function to print key/value pairs
<div>
<?php echo getKeyValuePairs(); ?>
</div>

Array and loop PHP

I'm really new new to php. I consider myself alright at Java, but wanted to get more into web stuff. I like HTML and CSS well enough, but I'm having a lot of trouble with php.
I'm writing a really basic php code. I want it to get info from a user (via form) and add it to an array in php (POST). I then would like to store the array as a session variable and write a for loop that prints out each index in an HTML list.
ISSUES:
1. I don't have a good handle on SESSION, so not sure how to store the array as a session variable.
2. I'm not sure how to reference a specific index of an array in php. I've sorta done it in a java way here, but that needs to change.
--CODE--
<html>
<body>
<form action="welcome.php" method="post">
Name: <input type="text" name="name"><br>
<input type="submit">
</form>
</body>
</html>
<?php
$stack = array("");
array_push($stack, $_POST[name]);
for(i < $stack.length){
print_r($stack[i]);
}
?>
To access session variables is easy:
First, you need to call the method session_start() (Make sure, you call it, before sending any HTTP header).
After calling the session_start() method, you will have access to the $_SESSION associative array. You will be able to append anything to this array.
The syntax of the for loop in PHP is as follows:
foreach (array_expression as $value)
statement
or
foreach (array_expression as $key => $value)
statement
I hope that it helps.
First let's see the lines of code in PHP you have written:
I.
$stack = array("");
This creates an array called $stack with a single element of "". $stack[0] will have the value of "". You can name the elements of an associated array, like this:
$stack = array("name" => "value");
In this case $stack["name"] will be "value".
II.
array_push($stack, $_POST[name]);
This is incorrect, since name is not a variable, nor a string. You probably meant:
array_push($stack, $_POST["name"]);
this would have written $_POST["name"] at the end of your array having "", so $stack[1] would have been whatever the value of $_POST["name"]; was.
III.
for(i < $stack.length){
This is incorrect syntax. You have meant
for($i = 0; $i < count($stack); $i++){
Note how $ is put in front of all variables and how similar this for cycle is to a Java for.
IV.
print_r($stack[i]);
Incorrect, you need the the cash ($), otherwise your variables will not cooperate.
print_r($stack[$i]);
You, however, do not check whether this is a POST request or a GET. When the user loads the page, it will be a GET request and when he submits the form, it will be a POST request. The first (GET) request will not have $_POST members ($_POST will be empty), as the form was not submitted yet. And if you check whether it is a POST request, you need to check whether "name" is present in $_POST:
<html>
<body>
<form action="welcome.php" method="post">
Name: <input type="text" name="name"><br>
<input type="submit">
</form>
</body>
</html>
<?php
if ($_SERVER['REQUEST_METHOD'] === 'POST') { //it is a post
if (isset($_POST["name"])) { //name is found inside $_POST
echo "Name is " . $_POST["name"];
}
}
?>
Question1:
$_SESSION is an array, like $stack. You can do something like this:
$_SESSION["name"] = $_POST["name"];
This will create a new element of $_SESSION with the index of "name", however, before such an assignment, you need to make sure the session was started.
Question2:
You reference it by the name of the index, just like in Java, however, in PHP you can have textual indexes as well if you want, while in Java you can only use integers.
Just to quickly update the code you have, to make it somewhat workable:
Html code
<html>
<body>
<form action="welcome.php" method="post">
Name: <input type="text" name="name"><br>
<input type="submit">
</form>
</body>
</html>
Php code
<?php
$stack = array("");
if(isset($_POST['name'])){
array_push($stack, $_POST['name']);
for($i=0; $i < count($stack); $i++){
echo($stack[$i]);
}
}
?>
Assuming this is all in welcome.php.

How to get vars out of a looped html form?

I got a html form which i loop like this:
for($i=0;$i<10;$i++){
echo '<input type="text" name="field'.$i.'">';
}
then i make and hidden input with a count var which says that there are 10 such input fields. but now i hav $field0 to $field9 and i do not know how i can get the input in a for loop again.
thanks for your help!
Use names like this in your input fields: ...'field['.$i.']'...
This way in your $_POST these will show up in an array for you, and you can loop over them like:
foreach ($_POST['field'] as $key => $value)
{
}
First of all you should use $_POST to get your form data. then you can make this by doing
for($i=0;$i<$_POST["count"];$i++) {
$var = $_GET["field".$i];
//do something
}
I assume that you have a count variable in $_POST["count"]
2nd you could better use Arrays in your looped form
<input type="text" name="field[0]">
then you have an array in $_POST["field"] with $_POST["field"][0] and $_POST["field"][1] etc...
but to answer just you wanted you can also use variable variables:
here a sample which should make this clear
$a1 = "What";
$a2 = " are";
$a3 = " you";
$a4 = " doing?";
for($i=1;$i<=4;$i++){
$txt .= ${"a".$i};
echo $txt;
}
takes as output
"What are you doing?"
:)
in your loop:
echo '<input type="text" name="field['.$i.']">';
then when you process this form when it's submitted:
$fields = $_POST['field'];
the "field" variable will be sent as an array to PHP

how to store variable values over multiple page loads

I'm making a php script that stores 3 arrays: $images, $urls, $titles based on the input data of the form within the php file.
I want to print the values of these arrays in the first part of the page and then to pre-fill the form's input fields with the value of the arrays. Also when a user modifies an input field and clicks on "Save" the page should reload with the modfied version.
My problem is that on each call of the php file in a browser the value of the variables gets deleted. Is there a way to store the values of the array so that the form always gets pre-filled with the last saved values?
<?php
//save the arrays with the form data
$images = array($_POST["i0"],$_POST["i1"],$_POST["i2"],$_POST["i3"]);
$urls = array($_POST["u0"],$_POST["u1"],$_POST["u2"],$_POST["u3"]);
$titles = array($_POST["t0"],$_POST["t1"],$_POST["t2"],$_POST["t3"]);
//print the arrays
print_r($images);
print_r($urls);
print_r($titles);
//create the form and populate it
echo "<p><form method='post' action='".$_SERVER['PHP_SELF']."';";
$x = 0;
while ($x <= 3) {
echo"<div>
<input name='i".$x."' type='text' value='".$images[$x]."'>
<input name='u".$x."' type='text' value='".$urls[$x]."'>
<input name='t".$x."' type='text' value='".$titles[$x]."'>";
$x++;
}
?>
<br>
<input type="submit" name="sumbit" value="Save"><br>
</form>
Store the variables in a PHP session.
session_start();
$_SESSION['images'] = $images;
Then on next (or any other) page, you can retrieve the values as:
session_start();
$images = $_SESSION['images'];
Changing the scope of the variables to a larger scope, might do the trick. Also, check if you have a post request before updating the values.
<?php
if(sizeof($_POST) >0)
{
//UPDATE VALUES
}
?>
If you want a permanent storage of state, between different pages, you should use sessions, by putting session_start(); in the start of your script. After this, every variable $_SESSION[$x] will be persisted, and will be available to your scripts.
However, in this particular case, answering your question: "Is there a way to store the values of the array so that the form always gets pre-filled with the last saved values?", it is easier to just use the $_POST variable if it exists already:
<?php
if(!$_POST){
$_POST = array();
foreach(array("i0","i1","i2","i3") as $i) $_POST[$i]="";
foreach(array("u0","u1","u2","u3") as $i) $_POST[$i]="";
foreach(array("t0","t1","t2","t3") as $i) $_POST[$i]="";
}
foreach($_POST as $k=>$v) filter_input(INPUT_POST,$k,FILTER_SANITIZE_SPECIAL_CHARS);
//save the arrays with the form data
$images = array($_POST["i0"], $_POST["i1"], $_POST["i2"], $_POST["i3"]);
$urls = array($_POST["u0"], $_POST["u1"], $_POST["u2"], $_POST["u3"]);
$titles = array($_POST["t0"], $_POST["t1"], $_POST["t2"], $_POST["t3"]);
//print the arrays
print_r($images);
print_r($urls);
print_r($titles);
//create the form and populate it
echo "<p><form method='post' action='".$_SERVER['PHP_SELF']."';";
$x = 0;
while ($x <= 3) {
echo"<div>
<input name='i".$x."' type='text' value='".$images[$x]."'>
<input name='u".$x."' type='text' value='".$urls[$x]."'>
<input name='t".$x."' type='text' value='".$titles[$x]."'>";
$x++;
}
?>
<br>
<input type="submit" name="sumbit" value="Save"><br>
</form>
Note: this line foreach($_POST as $k=>$v) filter_input(INPUT_POST,$k,FILTER_SANITIZE_SPECIAL_CHARS);
should be enough to protect you from basic XSS attacks.
Note also that in general, it is best to follow the pattern of reloading pages with GET after POST, which makes you less susceptible to form resubmitions, in which case using sessions for storage is the better solution.
What brought me here was somewhat different kind of beast. I had problem with subsequent post request from AXIS IP camera and needed to preserve last file name across requests. In case that someone stumble here looking for some way to cache variables and SESSION is not an option maybe should look at Alternative PHP Cache:
Note: Unlike many other mechanisms in PHP, variables stored using
apc_store() will persist between requests (until the value is removed
from the cache).
http://php.net/manual/en/book.apc.php
Use sessions: http://php.net/manual/en/function.session-start.php
You can use sessions to store values and write rules to refill form fields after validations on data submit. Also function isset() is very helpful to avoid "not defined" errors.
The solution you are looking for is the session. Use $_SESSION to store value of Your variables. For example, at the end of script:
$_SESSION['images'] = $images;
and in form's input:
<input name='i".$x."' type='text' value='".(isset($_SESSION['images']) ?
$_SESSION['images'] : '')."'>

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