how to make variable available in all files [duplicate] - php

It seems pretty simple but I can't find a good way to do it.
Say in the first page I create a variable
$myVariable = "Some text";
And the form's action for that page is "Page2.php". So in Page2.php, how can I have access to that variable? I know I can do it with sessions but I think it's too much for a simple string, and I do only need to pass a simple string (a file name).
How can I achieve this?
Thanks!

HTML / HTTP is stateless, in other words, what you did / saw on the previous page, is completely unconnected with the current page. Except if you use something like sessions, cookies or GET / POST variables. Sessions and cookies are quite easy to use, with session being by far more secure than cookies. More secure, but not completely secure.
Session:
//On page 1
$_SESSION['varname'] = $var_value;
//On page 2
$var_value = $_SESSION['varname'];
Remember to run the session_start(); statement on both these pages before you try to access the $_SESSION array, and also before any output is sent to the browser.
Cookie:
//One page 1
$_COOKIE['varname'] = $var_value;
//On page 2
$var_value = $_COOKIE['varname'];
The big difference between sessions and cookies is that the value of the variable will be stored on the server if you're using sessions, and on the client if you're using cookies. I can't think of any good reason to use cookies instead of sessions, except if you want data to persist between sessions, but even then it's perhaps better to store it in a DB, and retrieve it based on a username or id.
GET and POST
You can add the variable in the link to the next page:
Page2
This will create a GET variable.
Another way is to include a hidden field in a form that submits to page two:
<form method="get" action="page2.php">
<input type="hidden" name="varname" value="var_value">
<input type="submit">
</form>
And then on page two:
//Using GET
$var_value = $_GET['varname'];
//Using POST
$var_value = $_POST['varname'];
//Using GET, POST or COOKIE.
$var_value = $_REQUEST['varname'];
Just change the method for the form to post if you want to do it via post. Both are equally insecure, although GET is easier to hack.
The fact that each new request is, except for session data, a totally new instance of the script caught me when I first started coding in PHP. Once you get used to it, it's quite simple though.

Thanks for the answers above. Here's how I did it, I hope it helps those who follow. I'm looking to pass a registration number from one page to another, hence regName and regValue:
Create your first page, call it set_reg.php:
<?php
session_start();
$_SESSION['regName'] = $regValue;
?>
<form method="get" action="get_reg.php">
<input type="text" name="regName" value="">
<input type="submit">
</form>
Create your second page, call it get_reg.php:
<?php
session_start();
$regValue = $_GET['regName'];
echo "Your registration is: ".$regValue.".";
?>
<p>Back to set_reg.php
Although not as comprehensive as the answer above, for my purposes this illustrates in simple fashion the relationship between the various elements.

Passing data in the request
You could either embed it as a hidden field in your form, or add it your forms action URL
echo '<input type="hidden" name="myVariable" value="'.
htmlentities($myVariable).'">';
or
echo '<form method="POST" action="Page2.php?myVariable='.
urlencode($myVariable).'">";
Note this also illustrates the use of htmlentities and urlencode when passing data around.
Passing data in the session
If the data doesn't need to be passed to the client side, then sessions may be more appropriate. Simply call session_start() at the start of each page, and you can get and set data into the $_SESSION array.
Security
Since you state your value is actually a filename, you need to be aware of the security ramifications. If the filename has arrived from the client side, assume the user has tampered with the value. Check it for validity! What happens when the user passes the path to an important system file, or a file under their control? Can your script be used to "probe" the server for files that do or do not exist?
As you are clearly just getting started here, its worth reminding that this goes for any data which arrives in $_GET, $_POST or $_COOKIE - assume your worst enemy crafted the contents of those arrays, and code accordingly!

There are three method to pass value in php.
By post
By get
By making session variable
These three method are used for different purpose.For example if we want to receive our value on next page then we can use 'post' ($_POST) method as:-
$a=$_POST['field-name'];
If we require the value of variable on more than one page than we can use session variable as:-
$a=$_SESSION['field-name];
Before using this Syntax for creating SESSION variable we first have to add this tag at the very beginning of our php page
session_start();
GET method are generally used to print data on same page which used to take input from user. Its syntax is as:
$a=$_GET['field-name'];
POST method are generally consume more secure than GET because when we use Get method than it can display the data in URL bar.If the data is more sensitive data like password then it can be inggeris.

try this code
using hidden field we can pass php varibale to another page
page1.php
<?php $myVariable = "Some text";?>
<form method="post" action="page2.php">
<input type="hidden" name="text" value="<?php echo $myVariable; ?>">
<button type="submit">Submit</button>
</form>
pass php variable to hidden field value so you can access this variable into another page
page2.php
<?php
$text=$_POST['text'];
echo $text;
?>

Sessions would be the only good way, you could also use GET/POST but that would be potentially insecure.

**page 1**
<form action="exapmple.php?variable_name=$value" method="POST">
<button>
<input type="hidden" name="x">
</button>
</form>`
page 2
if(isset($_POST['x'])) {
$new_value=$_GET['variable_name'];
}

It works.
Send data throw URL, without form.
$upit = "SELECT * FROM usluga";
$data = $mysql->query($upit);
while ($row = mysqli_fetch_object($data))
{
echo "<a href='"."index.php?tretmanId=$row->tretman_id"."'>$row->naziv</a>";
echo "<br><br>";
}
and you can get this value on the target page with "$_GET['name from URL']", like this
$TrermanIdFromUrl = $_GET['tretmanId'];

You can for example call the page you want by including variables in the url:
header("Location: ../signup.php?newpwd=passwordupdated");
And on your signup.php page, you would have
if (isset($_GET['newpwd']) && $_GET['newpwd'] == "passwordupdated") {
//code here
}

Related

Pass array from one php page to another php page [duplicate]

It seems pretty simple but I can't find a good way to do it.
Say in the first page I create a variable
$myVariable = "Some text";
And the form's action for that page is "Page2.php". So in Page2.php, how can I have access to that variable? I know I can do it with sessions but I think it's too much for a simple string, and I do only need to pass a simple string (a file name).
How can I achieve this?
Thanks!
HTML / HTTP is stateless, in other words, what you did / saw on the previous page, is completely unconnected with the current page. Except if you use something like sessions, cookies or GET / POST variables. Sessions and cookies are quite easy to use, with session being by far more secure than cookies. More secure, but not completely secure.
Session:
//On page 1
$_SESSION['varname'] = $var_value;
//On page 2
$var_value = $_SESSION['varname'];
Remember to run the session_start(); statement on both these pages before you try to access the $_SESSION array, and also before any output is sent to the browser.
Cookie:
//One page 1
$_COOKIE['varname'] = $var_value;
//On page 2
$var_value = $_COOKIE['varname'];
The big difference between sessions and cookies is that the value of the variable will be stored on the server if you're using sessions, and on the client if you're using cookies. I can't think of any good reason to use cookies instead of sessions, except if you want data to persist between sessions, but even then it's perhaps better to store it in a DB, and retrieve it based on a username or id.
GET and POST
You can add the variable in the link to the next page:
Page2
This will create a GET variable.
Another way is to include a hidden field in a form that submits to page two:
<form method="get" action="page2.php">
<input type="hidden" name="varname" value="var_value">
<input type="submit">
</form>
And then on page two:
//Using GET
$var_value = $_GET['varname'];
//Using POST
$var_value = $_POST['varname'];
//Using GET, POST or COOKIE.
$var_value = $_REQUEST['varname'];
Just change the method for the form to post if you want to do it via post. Both are equally insecure, although GET is easier to hack.
The fact that each new request is, except for session data, a totally new instance of the script caught me when I first started coding in PHP. Once you get used to it, it's quite simple though.
Thanks for the answers above. Here's how I did it, I hope it helps those who follow. I'm looking to pass a registration number from one page to another, hence regName and regValue:
Create your first page, call it set_reg.php:
<?php
session_start();
$_SESSION['regName'] = $regValue;
?>
<form method="get" action="get_reg.php">
<input type="text" name="regName" value="">
<input type="submit">
</form>
Create your second page, call it get_reg.php:
<?php
session_start();
$regValue = $_GET['regName'];
echo "Your registration is: ".$regValue.".";
?>
<p>Back to set_reg.php
Although not as comprehensive as the answer above, for my purposes this illustrates in simple fashion the relationship between the various elements.
Passing data in the request
You could either embed it as a hidden field in your form, or add it your forms action URL
echo '<input type="hidden" name="myVariable" value="'.
htmlentities($myVariable).'">';
or
echo '<form method="POST" action="Page2.php?myVariable='.
urlencode($myVariable).'">";
Note this also illustrates the use of htmlentities and urlencode when passing data around.
Passing data in the session
If the data doesn't need to be passed to the client side, then sessions may be more appropriate. Simply call session_start() at the start of each page, and you can get and set data into the $_SESSION array.
Security
Since you state your value is actually a filename, you need to be aware of the security ramifications. If the filename has arrived from the client side, assume the user has tampered with the value. Check it for validity! What happens when the user passes the path to an important system file, or a file under their control? Can your script be used to "probe" the server for files that do or do not exist?
As you are clearly just getting started here, its worth reminding that this goes for any data which arrives in $_GET, $_POST or $_COOKIE - assume your worst enemy crafted the contents of those arrays, and code accordingly!
There are three method to pass value in php.
By post
By get
By making session variable
These three method are used for different purpose.For example if we want to receive our value on next page then we can use 'post' ($_POST) method as:-
$a=$_POST['field-name'];
If we require the value of variable on more than one page than we can use session variable as:-
$a=$_SESSION['field-name];
Before using this Syntax for creating SESSION variable we first have to add this tag at the very beginning of our php page
session_start();
GET method are generally used to print data on same page which used to take input from user. Its syntax is as:
$a=$_GET['field-name'];
POST method are generally consume more secure than GET because when we use Get method than it can display the data in URL bar.If the data is more sensitive data like password then it can be inggeris.
try this code
using hidden field we can pass php varibale to another page
page1.php
<?php $myVariable = "Some text";?>
<form method="post" action="page2.php">
<input type="hidden" name="text" value="<?php echo $myVariable; ?>">
<button type="submit">Submit</button>
</form>
pass php variable to hidden field value so you can access this variable into another page
page2.php
<?php
$text=$_POST['text'];
echo $text;
?>
Sessions would be the only good way, you could also use GET/POST but that would be potentially insecure.
**page 1**
<form action="exapmple.php?variable_name=$value" method="POST">
<button>
<input type="hidden" name="x">
</button>
</form>`
page 2
if(isset($_POST['x'])) {
$new_value=$_GET['variable_name'];
}
It works.
Send data throw URL, without form.
$upit = "SELECT * FROM usluga";
$data = $mysql->query($upit);
while ($row = mysqli_fetch_object($data))
{
echo "<a href='"."index.php?tretmanId=$row->tretman_id"."'>$row->naziv</a>";
echo "<br><br>";
}
and you can get this value on the target page with "$_GET['name from URL']", like this
$TrermanIdFromUrl = $_GET['tretmanId'];
You can for example call the page you want by including variables in the url:
header("Location: ../signup.php?newpwd=passwordupdated");
And on your signup.php page, you would have
if (isset($_GET['newpwd']) && $_GET['newpwd'] == "passwordupdated") {
//code here
}

PHP Passing a variable to another page then pass it back to the original page

This is a little bit quite confusing to explain. I want to know how to store a string into a variable and pass it to the next page and in that next page pass that variable again to another variable then that variable will pass it back to the original page.
Example:
I have two PHP pages. lets call them form1.php and form2.php
In form1.php, I will input Hello and it will be stored in var1.
var1 will be sent to form2.php and it is stored in var2 in form2.php as well.
in form2.php, var2 is passed to var3 and var3 will be sent back to form1.php.
And output Hello in form1.php using var3 not var1.
This is where I got stuck. Can't figure out how to do this. Please comment if the question is a little vague, even I cant seem to figure it out myself. Thanks.
You want to use Sessions. With sessions you can pass variables to a different page.
You have to start sessions on both pages.
session_start();
After that you can store variables in a session.
For example:
$var1 = $_SESSION['name'];
Now you can use IT in every page with session_start();
Well if you are actually using forms then you should be able to just grab the values of the variables in $_GET or $_POST (depending on the method used by the forms). You could just store the values in hidden inputs the user doesn't see and use that to pass things around:
<input type = "hidden" value = "<?php echo $_GET['var2'];?>" />
If this isn't what you need you may want to look at sessions to maintain state throughout your site.
My understanding is that you want to pass some data between two distinct forms - you need to consider that these forms are completely independent form each other so you will need to pass data back to the browser or leverage a server side session.
Depending on your use case you could:
Submit data to form1.php - this would then return a form with additional fields ready for submision to form2.php
The trick here - is that data that needs to be passed between forms would be included in the generation of the second form as hidden elements.
<input type="hidden" id="var1" value="data from form1" />
You can have as many hidden types as you need.
Be aware this approach is not very secure - so you may need consider defences e.g. csrf - or using sessions and tracking the data on the server side.
From what I understand, you need two forms to send data from the first to the second and from the second back to the first. In this communication, you don't need the third var, how about this?
form1.php
<form method=POST action="form2.php">
<input type="text" name="var1" value="<?=#$_POST["var2"];?>">
<input type="submit" value="Continue">
</form>
form2.php
<form method=POST action="form1.php">
<input type="text" name="var2" value="<?=#$_POST["var1"];?>">
<input type="submit" value="Continue">
</form>

Reusing a $_GET variable in a $_POST?

I have my index.php page that sends values over to edit.php via $_GET/html link. I can see the values go, including the table ID I want to use using echo statements. The problem is that I need the specific ID value used in another form using a submit form($_POST). I've tried different approaches including SESSION, making the $ID = $_GET.... I'm pulling my hair out.
Here is the order of things:
//Edit link on index.php sends the id='summary_id', which works
<td align="center">Edit</td>
//Edit.php grabs the variable and I set it to that variable
if(isset($_GET['id']))
echo "<pre>Value of GET \$_GET:</br>";print_r($_GET);echo"</pre>";
{
$summary_id = $_GET['id'];
$summary_id = $_POST['summary_id'];
But, when I try to use $summary_id in a form (using $_POST this time), I get no value. I'm not sure if what I'm trying to do is "legal". I've tried sending the summary_id as a hidden value in the form, but again, nothing is going through. I'm losing it after that initial $_GET.
You are doing wrong.You are overwriting the variable that is not available $_POST['summary_id']
if you really want to use post method use this
<form action="edit.php" method="POST">
<input type="hidden" value="<?php echo $row['summary_id'];?>" name="summary_id"/>
<input type="submit" value="EDIT"/>
</form>
or you can use header() to post the value
You are overwriting your own variable. Also, it's clear from this that you don't actually have PHP errors turned on.
You could use $_REQUEST instead as it contains both $_GET and $_POST.

passing parameters from one php to multiple php

.I have three php pages:
page1.php
page2.php
page3.php
on page1.php i have this code:
<form id="try" method="post" action="page2.php">
Batch: <input id="batch" name="batch" type="text"/><br />
Dept: <input id="dept" name="dept" type="text"><br />
<input type="submit" />
</form>
on page2.php i am able to use the values inserted on page1.php by simply calling them using $_POST['batch']; and $_POST['dept'];
but what i want to do next is to pass the values of batch and dept from page2.php to page3.php. or maybe from page1.php to page2.php since i think it's just the same.
.Help pls! Thanks in adv
#kjy112 - i'm confused, since i am using
<form method="post">
should i be starting my session on page2.php by using the following:
session_start();
$_SESSION['batch'] = $_POST['batch'];
$_SESSION['dept'] = $_POST['dept'];
and then use
session_start();
$batch = $_SESSION['batch'];
to use it on page3.php?
Per #Crayon Violent: To use cookie-based sessions, session_start() must be called before outputing anything to the browser.
You'll need to use PHP SESSION you can get/set like this:
// page1.php
session_start();
$_SESSION['myvar'] = 'test';
//page2.php
session_start();
$myvar = $_SESSION['myvar'];
echo $myvar; //should be test;
//page3.php
session_start();
echo $_SESSION['myvar']; //should give u test still
make use of session variables.
you can save the $_POST values to a $_SESSION variable:
$_SESSION['POST'] = $_POST;
One way to move values from one script to another, and without worrying about which script is accessed in what order, is to use a session.
When your scripts start, you open the session. This gets you access to the $_SESSION superglobal, like $_POST. You can write to the $_SESSION array in one script and read it out in another. This is all handled on the server, so you can store any data you want into the session without worrying about the user seeing this data. It's very useful and is often used with multi part form, sites with logins, and to track user choices over as many pages as the user accesses.
just answering questions in comments
what do you mean by session_start() must be called before outputting
anything to the browser?
mean it's best practice to put session_start() directly after <?php
like <?php session_start(); and make sure that php starting tag is not after <html> tag.
will this also work if my purpose is to use batch and dept on SQL
queries?
yes, of course, just set all your parameters (sql, dept) in $_SESSION[''] variable.

PHP Pass variable to next page

It seems pretty simple but I can't find a good way to do it.
Say in the first page I create a variable
$myVariable = "Some text";
And the form's action for that page is "Page2.php". So in Page2.php, how can I have access to that variable? I know I can do it with sessions but I think it's too much for a simple string, and I do only need to pass a simple string (a file name).
How can I achieve this?
Thanks!
HTML / HTTP is stateless, in other words, what you did / saw on the previous page, is completely unconnected with the current page. Except if you use something like sessions, cookies or GET / POST variables. Sessions and cookies are quite easy to use, with session being by far more secure than cookies. More secure, but not completely secure.
Session:
//On page 1
$_SESSION['varname'] = $var_value;
//On page 2
$var_value = $_SESSION['varname'];
Remember to run the session_start(); statement on both these pages before you try to access the $_SESSION array, and also before any output is sent to the browser.
Cookie:
//One page 1
$_COOKIE['varname'] = $var_value;
//On page 2
$var_value = $_COOKIE['varname'];
The big difference between sessions and cookies is that the value of the variable will be stored on the server if you're using sessions, and on the client if you're using cookies. I can't think of any good reason to use cookies instead of sessions, except if you want data to persist between sessions, but even then it's perhaps better to store it in a DB, and retrieve it based on a username or id.
GET and POST
You can add the variable in the link to the next page:
Page2
This will create a GET variable.
Another way is to include a hidden field in a form that submits to page two:
<form method="get" action="page2.php">
<input type="hidden" name="varname" value="var_value">
<input type="submit">
</form>
And then on page two:
//Using GET
$var_value = $_GET['varname'];
//Using POST
$var_value = $_POST['varname'];
//Using GET, POST or COOKIE.
$var_value = $_REQUEST['varname'];
Just change the method for the form to post if you want to do it via post. Both are equally insecure, although GET is easier to hack.
The fact that each new request is, except for session data, a totally new instance of the script caught me when I first started coding in PHP. Once you get used to it, it's quite simple though.
Thanks for the answers above. Here's how I did it, I hope it helps those who follow. I'm looking to pass a registration number from one page to another, hence regName and regValue:
Create your first page, call it set_reg.php:
<?php
session_start();
$_SESSION['regName'] = $regValue;
?>
<form method="get" action="get_reg.php">
<input type="text" name="regName" value="">
<input type="submit">
</form>
Create your second page, call it get_reg.php:
<?php
session_start();
$regValue = $_GET['regName'];
echo "Your registration is: ".$regValue.".";
?>
<p>Back to set_reg.php
Although not as comprehensive as the answer above, for my purposes this illustrates in simple fashion the relationship between the various elements.
Passing data in the request
You could either embed it as a hidden field in your form, or add it your forms action URL
echo '<input type="hidden" name="myVariable" value="'.
htmlentities($myVariable).'">';
or
echo '<form method="POST" action="Page2.php?myVariable='.
urlencode($myVariable).'">";
Note this also illustrates the use of htmlentities and urlencode when passing data around.
Passing data in the session
If the data doesn't need to be passed to the client side, then sessions may be more appropriate. Simply call session_start() at the start of each page, and you can get and set data into the $_SESSION array.
Security
Since you state your value is actually a filename, you need to be aware of the security ramifications. If the filename has arrived from the client side, assume the user has tampered with the value. Check it for validity! What happens when the user passes the path to an important system file, or a file under their control? Can your script be used to "probe" the server for files that do or do not exist?
As you are clearly just getting started here, its worth reminding that this goes for any data which arrives in $_GET, $_POST or $_COOKIE - assume your worst enemy crafted the contents of those arrays, and code accordingly!
There are three method to pass value in php.
By post
By get
By making session variable
These three method are used for different purpose.For example if we want to receive our value on next page then we can use 'post' ($_POST) method as:-
$a=$_POST['field-name'];
If we require the value of variable on more than one page than we can use session variable as:-
$a=$_SESSION['field-name];
Before using this Syntax for creating SESSION variable we first have to add this tag at the very beginning of our php page
session_start();
GET method are generally used to print data on same page which used to take input from user. Its syntax is as:
$a=$_GET['field-name'];
POST method are generally consume more secure than GET because when we use Get method than it can display the data in URL bar.If the data is more sensitive data like password then it can be inggeris.
try this code
using hidden field we can pass php varibale to another page
page1.php
<?php $myVariable = "Some text";?>
<form method="post" action="page2.php">
<input type="hidden" name="text" value="<?php echo $myVariable; ?>">
<button type="submit">Submit</button>
</form>
pass php variable to hidden field value so you can access this variable into another page
page2.php
<?php
$text=$_POST['text'];
echo $text;
?>
Sessions would be the only good way, you could also use GET/POST but that would be potentially insecure.
**page 1**
<form action="exapmple.php?variable_name=$value" method="POST">
<button>
<input type="hidden" name="x">
</button>
</form>`
page 2
if(isset($_POST['x'])) {
$new_value=$_GET['variable_name'];
}
It works.
Send data throw URL, without form.
$upit = "SELECT * FROM usluga";
$data = $mysql->query($upit);
while ($row = mysqli_fetch_object($data))
{
echo "<a href='"."index.php?tretmanId=$row->tretman_id"."'>$row->naziv</a>";
echo "<br><br>";
}
and you can get this value on the target page with "$_GET['name from URL']", like this
$TrermanIdFromUrl = $_GET['tretmanId'];
You can for example call the page you want by including variables in the url:
header("Location: ../signup.php?newpwd=passwordupdated");
And on your signup.php page, you would have
if (isset($_GET['newpwd']) && $_GET['newpwd'] == "passwordupdated") {
//code here
}

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