using a foreach loop to initialize variables - php

I have built an empty associative array whos keynames refer to submitted post data. I can capture the postdata just fine, but I run into trouble trying to instantiate variables who's names match the array key.
for example:
$insArray = array('rUsername'=>'', 'rPass'=>'', 'rQuestion'=>'', 'rAnswer'=>'', 'rFName'=>'', 'rLName'=>'', 'rBDateD'=>'', 'rBDateM'=>'', 'rBDateY'=>'', 'rHCheck'=>'', 'rHCeckOption'=>'', 'rEmail'=>'');
foreach($insArray as $key=>$value){
if (filter_input(INPUT_POST, $key) != ''){
$key = stripslashes(filter_input(INPUT_POST, $key));
$insArray[$key] = $key;
}
}
First line creates the empty array, then the foreach loops through this array. Now it gets tricky.
filter_input(INPUT_POST, $key) captures the value located in the post data matching the current key, rUsername in this case
$key is where the problem lies. I want the NAME of the new variable to be the associative key name, for example I want to replace $key with $rUsername in the first iteration, $rPass in the second, and so on. I tried using two $$, but I know that's not right. Never tried doing this before, but it would be helpful if I could figure it out.
UPDATE:
This is the final code which was a combination of two of the answers provided.
if (isset($_POST['submit'])) {
//Build array of variables to be put into database
$insArray = array('rUsername'=>'', 'rPassword'=>'', 'rQuestion'=>'', 'rAnswer'=>'', 'rFName'=>'', 'rLName'=>'', 'rBDateD'=>'', 'rBDateM'=>'', 'rBDateY'=>'', 'rHCheck'=>'', 'rHCheckOption'=>'', 'rEmail'=>'');
foreach(array_keys($insArray) as $key){
$insArray[$key] = filter_input(INPUT_POST, $key);
$$key = filter_input(INPUT_POST, $key);
}
}
Gave me exactly the output I wanted, thanks guys!

You're not accessing $_POST at all, so all you're doing is taking some array members you defined yourself, filtering them for harmful POST characters (why would you attempt to inject your own code?) and then creating a new array from those self-defined key values.
If I'm guessing right at what you want, it should be this:
foreach(array_keys($insArray) as $key) {
$insArray[$key] = stripslashes(filter_input(INPUT_POST, $_POST[$key]));
}
The use of stripslashes suggests that you're on a braindead version of PHP which has magic_quotes enable. You should upgrade to a modern version of PHP and/or turn them off.

The solution is change
$key = stripslashes(filter_input(INPUT_POST, $key));
to
$$key = stripslashes(filter_input(INPUT_POST, $key));
See http://www.php.net/manual/en/language.variables.variable.php
Also, recheck your code, which are doing some mistakes..

If I understand you correctly, Im going to suggest this approach:
$defaultValues = array('rUsername'=>'', 'rPass'=>'', 'rQuestion'=>'', 'rAnswer'=>'', 'rFName'=>'', 'rLName'=>'', 'rBDateD'=>'', 'rBDateM'=>'', 'rBDateY'=>'', 'rHCheck'=>'', 'rHCeckOption'=>'', 'rEmail'=>'');
$values = array_map('stripslashes', array_merge($defaultValues, array_filter($_POST)));
extract($values, EXTR_SKIP);
echo $rUsername;
echo $rPass;
.........
By using the snippet above, you have to take into account the following
Im using the extract function with EXTR_SKIP so you dont overwrite existing variables. Make sure to only use the variables you need in your code and sanitize them appropietly.
By using array_filter on the $_POST superglobal im "erasing" all empty or null variables. so if an expected key was not sent via $_POST, it defaults to the value specified by the $defaultValues array.
I dont quite understand why you are using filter_input without the third parameter (filter constants).

Hope this will help, If not may be I have misunderstood the problem.
Instead of
$key = stripslashes(filter_input(INPUT_POST, $key));
$insArray[$key] = $key;
Try
$insArray[$key] =stripslashes(filter_input(INPUT_POST, $key));
Then after the foreach loop
extract($insArray);

Related

Pushing values from a $_Get query to a value using implode

I am attempting to use a for loop or for each loop to push the values from a get query to another variable. May I have some help with this approach?
Ok here is where I am:
for ($i = 0 ; i < $_GET['delete']; i++) {
$_jid [] = $_GET['delete'];
}
You don't actually need a loop here. If $_jid already is an array containing some values, consider just merging it with $_GET['delete'].
if (is_array($_jid)) {
$_jid = array_merge($_jid, $_GET['delete']);
}
If $_jid is not an array and doesn't exist except as a container for $_GET['delete'] you do can just assign the array. There is no need to loop at all.
$_jid = $_GET['delete'];
Of course in that case, you don't even need to copy it. You can just use $_GET['delete'] directly, in any context you planned to read from $_jid.
Update:
If the contents of $_GET['delete'] are originally 923,936, that is not an array to begin with, but rather a string. If you want an array out of it, you need to explode() it on assignment:
$_jid = explode(',', $_GET['delete']);
But if you intend to implode() it in the end anyway, there's obviously no need to do that. You already have exactly the comma-delimited string you want.
As you can see if you do a var_dump($_GET), the variable $_GET is a hashmap.
You can easily use a foreach loop to look through every member of it :
foreach($_GET as $get) // $get will successively take the values of $_GET
{
echo $get."<br />\n"; // We print these values
}
The code above will print the value of the $_GET members (you can try it with a blank page and dull $_GET values, as "http://yoursite.usa/?get1=stuff&get2=morestuff")
Instead of a echo, you can put the $_GET values into an array (or other variables) :
$array = array(); // Creating an empty array
$i = 0; // Counter
foreach($_GET as $get)
{
$array[$i] = $get; // Each $_GET value is store in a $array slot
$i++;
}
In PHP, foreach is quite useful and very easy to use.
However, you can't use a for for $_GET because it's a hashmap, not an array (in fact, you can, but it's much more complicated).
Hope I helped

all variables from url

I have a code like that:
session_start();
$user = $_GET['user'];
$mode = $_GET['mode'];
$id1 = $_GET['id1'];
$id2 = $_GET['id2'];
$id3 = $_GET['id3'];
$id4 = $_GET['id4'];
$id5 = $_GET['id5'];
$id6 = $_GET['id6'];
$id7 = $_GET['id7'];
$id8 = $_GET['id8'];
$dep= $mode;
switch ($dep)
{
case "3m":
$dep = "Text 1";
break;
case "all":
$dep = "More text";
break;
default:
$dep = "Text1";
}
There are more other cases. I think I will have more id's and cases soon. Is there a simpler way to get all id's from URL push them into PHP code for evaluating?
I have found a code foreach:
foreach($_GET as $key => $value) {
echo 'key is: <b>' . $key . '</b>, value is: <b>' .$value. '</b><br />';
}
And it gets all variables from URL, but how to change the code in order to have it like this:
$variable = $_GET['variable'];
Any help appreciated :)
Use arrays, that's exactly what they're for. Name the parameters in the URL like:
id[]=1&id[]=2&...
Then $_GET['id'] is an array which you can easily loop through.
Many ids means you're looking for an array of ids, not id1, id2, id3 etc. An array allows you to access them virtually the same way as $id[1], $id[2] etc, but without the headache of needing to herd hundreds of independent variables.
There's also no need to assign each value from $_GET into its own variable, you can use those values directly from $_GET. They're not getting any better by assigning them into individual variables.
Assuming I understood correctly and you want all GET variables to be actual variables you can use, there's a function extract to do that.
However, as noted in the documentation:
Do not use extract() on untrusted data, like user input (i.e. $_GET,
$_FILES, etc.). If you do, for example if you want to run old code
that relies on register_globals temporarily, make sure you use one of
the non-overwriting flags values such as EXTR_SKIP and be aware that
you should extract in the same order that's defined in variables_order
within the php.ini.
So basically you should not do this unless you have good reasons, and be careful if you do as to not overwrite any existing values.
However, if your alternative is to do this:
foreach($_GET as $key => $value) {
$$key=$value;
}
then extract is certainly better, as a) you can set it to not overwrite any existing variables, and b) you can have a prefix, so those imported variables can be distinguished. Like this:
extract ( $_GET, EXTR_SKIP);
For $user, $mode, $id which don't overwrite anything, or
extract ( $_GET, EXTR_PREFIX_ALL, 'user_input' );
for $user_input_mode, $user_input_user, $user_input_id etc.
function getIDs()
{
$ids = array();
if(isset($_GET['id']))
{
foreach($_GET['id'] as $key => $value)
{
$ids[$key] = $value;
}
}
return $ids;
}
If you can get your URL to send an array of id GET parameters to a PHP script you can just parse the $_GET['id'] array in the above function, assuming the URI looks like ?id[]=1&id[]=2&id[]=3
$ids = getIDs();
You can write
foreach($_GET as $key => $value) {
$$key=$value;
}
this will assign every key name as a varibale.

Calling PHP function in itself

In the following script function clean($data) calls it within it, that I understand but how it is cleaning data in the statement $data[clean($key)] = clean($value);??? Any help is appreciated.. I am trying to figure it out as I am new to PHP. Regards.
if (ini_get('magic_quotes_gpc')) {
function clean($data) {
if (is_array($data)) {
foreach ($data as $key => $value) {
$data[clean($key)] = clean($value);
}
} else {
$data = stripslashes($data);
}
return $data;
}
$_GET = clean($_GET);
$_POST = clean($_POST);
$_REQUEST = clean($_REQUEST);
$_COOKIE = clean($_COOKIE);
}
Your Question:
So if I undertsand correctly you want to know what is the function doing in the line
$data[clean($key)] = clean($value);
The Answer:
See the prime purpose of the function is to remove slashes from string with php's stripslashes method.
If the input item is an array then it tries to clean the keys of the array as well as the values of the array by calling itself on the key and value.
In php arrays are like hashmaps and you can iterate over the key and value both with foreach loop like following
foreach ($data as $key => $value) {....}
So if you want to summarize the algorithm in your code snippet it would be as under
Check if the input is array. If it is not then go to step 4
For each item of array clean the key and value by calling clean method on it (Recursively)
Return the array
clean the input string using stripslashes method
5 return the cleaned input
From my understanding it's not cleaning the key but creates a new element with a clean key while the uncleaned key remains.
$a['foo\bar'] : val\ue
becomes
$a['foo\bar'] : val\ue
$a['foobar'] : value
Someone correct me if im wrong.
Maybe you'll understand the code better if it's put this way:
foreach ($data as $key => $value) {
$key = clean($key); // Clean the key, the
$value = clean($value); // Clean the value
$data[$key] = $value; // Put it in the array that will be returned
}
Assuming you have an array like this:
$_POST = array(0 => 'foo', 1 => array('bar' => 'baz'));
the following will happen:
Call clean($_POST);
call clean 0
call clean 'foo'
$return[0] = 'foo'
call clean 1
call clean 'bar'
call clean 'baz'
$return[1] = array('bar' => 'baz');
You should probably read this: http://www.codewalkers.com/c/a/Miscellaneous/Recursion-in-PHP/
The main purpose of the function is to clean an associative array or a single variable. An associative array is an array where you define keys and values for that keys; so are special arrays used in PHP like $_GET $_POST and so on.
The meaning of "cleaning" is to check whether magic quotes are active - this causes some characters in these arrays to be escaped with backslashes when you post dynamic data to a PHP page.
$_GET["Scarlett"] = "O' Hara" becomes with magic quotes $_GET["Scarlett"] = "O\' Hara"
So if magic quotes are active, the function takes care of this, and slashes are stripped so that the strings retain their correct, not escaped value.
The algorithm checks if the data passed to the function is an array, if not it cleans directly the value.
$string = "Escapes\'in\'a string";
clean($string);
is it an array? No. Then return stripslashes(my data)
$array = array("key\'with\'escapes"=>"value\'with\'escapes", "another\'key"=>"another value");
clean($array)
is it an array? Yes. So cycle through each key/value pair with foreach, take the key and clean it like the first example; then take the value and do the same and put the cleaned versions in the array.
As you see the function has two different behaviours differentiated by that "if" statement.
If you pass an array, you activate the second behaviour that in turns passes couples of strings, not arrays, triggering the first behaviour.
My thought is that this function doesn't work properly, though. Anyone got the same sensation? I have it not tested yet but it seems it's not "cleaning" the key/values in the sense of replacing them, but adds the cleaned versions along the uncleaned ones.

PHP - Save value AND name using $_POST

I'm currently using the following format to save a value from an HTML form $item_name=$_POST['item_name'];
This saves the value, but how to I also save the name attribute in a variable?
Thanks in advance!
Assuming you want to store each element of $_POST variable as a key-value pair, then you can try:
$var = array();
foreach($_POST as $key => $val) {
$var[$key] = $val;
}
I'm saving a lot of values and want to avoid typing each one out.
Please, make your mind first.
Global variables are intended to be typed by hand.
If you want some automated processing - just keep them in a form of array.
Looks like rdt.exe's answer is what you're looking for.
maye you noticed you have to use the name to access the $_POST-array and get the value. if you want to store the name in a variable, too, just do:
$item_name_name = 'item_name';
$item_name_value = $_POST[$item_name_name];
you could also use some kind of loop to dynamically create variables with the according names like this:
foreach( $_POST as $name => $value ){
$$name = $value;
}
both ways are some kind of unnecessary and useless in my opinion, but you havn't stated what exactly you're trying to achive - so maybe this helps.
An alternative approach:
$keysarray = array_keys ( $_POST);
print_r( $keysarray);
This will give you all the keys in array
The function you are looking for is called extract.
This will create variables for all the $key=>$val pairs in the array.
$_EXAMPLE = array('bird' => 'chicken', 'dog' => 'greyhound');
export($_EXAMPLE);
echo $bird; # prints "chicken"
echo $dog; # prints "greyhound"
Watch out though - this is a huge security risk. So are the solutions described in some of the other answers.
The problem with doing something like this is that a user can tamper with the POST data, and set parameters other than the ones she is supposed to set. If they set variables that are actually variable names in your application, those variables can be overwritten.
$is_admin = false;
$_EXAMPLE = array('bird' => 'chicken', 'dog' => 'greyhound', 'is_admin' => 'true');
export($_EXAMPLE);
if ($is_admin) { # this will now evaluate to true.
# do sensitive stuff...
}

A $_GET input parameter that is an Array

I'm trying to pass 3 parameter to a script, where the 3rd parameter $_GET['value3'] is supposed to be an array
$_GET['value1']
$_GET['value2']
$_GET['value3'] //an array of items
I'm calling the script like this: (notice my syntax for value3, I'm not sure it's correct)
http://localhost/test.php?value1=test1&value2=test2&value3=[the, array, values]
I then use a foreach to hopefully loop through the third parameter value3 which is the array
//process the first input $_GET['value1']
//process the second input $_GET['value2']
//process the third input $_GET['value3'] which is the array
foreach($_GET['value3'] as $arrayitem){
echo $arrayitem;
}
but I get the error Invalid argument supplied for foreach()
I'm not sure if my methodology is correct. Can some clarify how you'd go about doing the sort of thing
There is no such thing as "passing an array as a URL parameter" (or a form value, for that matter, because this is the same thing). These are strings, and anything that happens to them beyond that is magic that has been built into your application server, and therefore it is non-portable.
PHP happens to support the &value3[]=the&value3[]=array&value3[]=values notation to automagically create $_GET['value3'] as an array for you, but this is special to PHP and does not necessarily work elsewhere.
You can also be straight-forward and go for a cleaner URL, like this: value3=the,array,values, and then use explode(',', $_GET['value3']) in your PHP script to create an array. Of course this implies that your separator char cannot be part of the value.
To unambiguously transport structured data over HTTP, use a format that has been made for the purpose (namely: JSON) and then use json_decode() on the PHP side.
try
http://localhost/test.php?value1=test1&value2=test2&value3[]=the&value3[]=array&value3[]=values
For arrays you need to pass the query parameters as
value3[]=abc&value3[]=pqr&value3[]=xyz
You can cast the name of the index in the string too
?value1[a]=test1a&value1[b]=test1b&value2[c][]=test3a&value2[c][]=test3b
would be
$_GET['value1']['a'] = test1a
$_GET['value1']['b'] = test1b
$_GET['value2']['c'] = array( 'test3a', 'test3b' );
http://php.net/manual/en/reserved.variables.get.php
Check out the above link..
You will see how the GET method is implemented.
What happens is that the URL is taken, it is delimited using '&' and then they are added as a key-value pair.
public function fixGet($args) {
if(count($_GET) > 0) {
if(!empty($args)) {
$lastkey = "";
$pairs = explode("&",$args);
foreach($pairs as $pair) {
if(strpos($pair,":") !== false) {
list($key,$value) = explode(":",$pair);
unset($_GET[$key]);
$lastkey = "&$key$value";
} elseif(strpos($pair,"=") === false)
unset($_GET[$pair]);
else {
list($key, $value) = explode("=",$pair);
$_GET[$key] = $value;
}
}
}
return "?".((count($_GET) > 0)?http_build_query($_GET).$lastkey:"");
}
Since, they are added as a key-value pair you can't pass array's in the GET method...
The following would also work:
http://localhost/test.php?value3[]=the&value3[]=array&value3[]=values
A more advanced approach would be to serialize the PHP array and print it in your link:
http://localhost/test.php?value3=a:3:{i:0;s:3:"the";i:1;s:5:"array";i:2;s:6:"values";}
would, essentially, also work.

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