PHP - Variable Wont Return From Between Classes

I think I might have already asked something similar, but...

my code has:

$ip = gethostbyaddr($_SERVER['REMOTE_ADDR']);
$host = $_SERVER['HTTP_HOST'];

my field header for "$host" is "VISITOR DOMAIN ADDRESS".  I'm not sure what I was thinking.  That's not possible to capture is it?  Last I read, and I think someone here told me, it is only possible to capture the IP and server name of the requesting computer?  the var $ip in my report, for instance, returns:

173-28-199-198.client.mchsi.com

if I visit the page, and that is the name of the server assigned to my ISP.  on PHP's doc page, there are the vars REMOTE_HOST and REMOTE_USER and I haven't tried those.  Their example does not list any return value for those vars.  what do they return?

Edited November 23, 2019 by ajetrumpet

I've been spending long hours learning about classes and their magic methods. I just came across a tutorial which showed a constructor like this:

class Device {
    //...
    public function  __construct(Battery $battery, $name) {
        // $battery can only be a valid Battery object
        $this->battery = $battery;
        $this->name = $name;
        // connect to the network
        $this->connect();
    }
    //...
}

the Battery part instantly caught my attention. Here had previously made a Battery class (and a more complete Device class) but the next thing he did really caught my interest:

$device = new Device(new Battery(), 'iMagic');
// iMagic connected
echo $device->name;
// iMagic

what the hell is going on here? Is this another way to include the methods and properties of one class into another class, in order words is this the same thing as:

class Device extends Battery

I don't think so because this new Battery() thing looks more like its creating an object inside the Device object. Previously the only way I could to that was to type $battery = new Battery() inside one of my methods. But this looks like hes doing something different. Can anyone explain whats going on here?   The whole tutorial is he http://code.tutsplus...-php--net-13085 in the main Device method he has a premade $battery variable to hold the Battery object. Sometimes I have multiple classes containing functions which I'd like to include in my main class. I can only extend one class, so I usually extent a class containing only properties, no methods. I still don't know what difference making that info class abstract is, I'd appreciate if anyone could tell me.   Also I'd love to know what the point in static methods is. I've never used them because I've never seen the point. Is it just to make it easier to call the methods because you don't need to create an object instance to call them? Sorry for the extra questions, the first one is what I'm really wondering about.    

I have found postings close, but not close enough to find my error.
I am looking up data from a MySql table and putting it in a dropdown box on a form. I can select the item, but apparently not really. I am not able to echo it, or post it to a record.
I'm sure I am missing something simple, but...
Code attached if anyone can show me the errors of my ways.
Thank you.

OK, have no idea what's going on... I've done this a million times... why wont this output!??
I must have a major brain meltdown and dont know it yet!!!

Code: [Select]
<?php

// this echoes just fine:
echo $_POST['testfield'];


// but this wont echo:
echo 
if (isset($_POST['testfield']))
{
$_POST['testfield'] = $test;
}
echo $test;


/// or even this DOESNT echo either!:
$_POST['testfield'] = $test;
echo $test;

?>

Hey,
 
 I wanted to know if there is any difference between catching a return value and assigning into a variable, and just catching the value when when you just simply call the function on its own.

Here is what I mean below

In the first example I called the return by simple calling the function. In the second example I catched the return value through a variable, and then echoed it out.

Code: [Select]
<?php
// Example 1 
function text (){

$string = "this is a string </br>";
return $string;}

echo text();

// Example 2
function text (){

$string = "this is a string </br>";
return $string;

}

$new_value = text();
echo $new_value;

}
?>

Not sure how to describe what I'm trying to do here in the title, but here goes with what I am trying to accomplish.

I've got a few hundred lines of code in total so far, so I'll try to keep it as short as I can. I've got an application that I am programming using classes for each module and right now I am coding the base classes that I need in order for it to run (database, errors, logging, etc). What I'm doing for my database class is I have a query factory and it extends the MySQLi class so I can process, clean and code the rest of my app faster. I also have another, unrelated class "Error", which will be used for processing errors I might come across.

I'd rather do it this way instead of having to call trigger_error and error_log every time there is an error. I'd also not like to have to call a new instance of an object every time I need to use something from that class. Is there any way I can call a class within a class and return it as an object for all the methods within the class?

I've tried the methods below, but no luck I've tried others, but I'm trying to keep it brief and get what I'm trying to do across.

<?php

class QueryFactory extends MySQLi {

public  $err = new error(); //Doesn't work.
public  $err = error(); //Nope.

#This is the function that I need the $err object for.
function set($fields, $newvals) {

if ( is_array($fields) && is_array($newvals) ) {

if ( count($fields) != count($newvals) ) {
//Instead of below, I want to do something like $err->('Array lengths must match for method', 256, $islogged = 1);
                              trigger_error('Array lengths must match for method', 256);
}

}
}

}


The thing is, I have a "run.inc.php" which does include and create new objects for running just the basic app and if I try to redeclare the error class in query.class.php, it gives me an error saying I can't do that, but if i try to call $err from the page that has all the classes defined it throws an error saying that my method is undeclared. I'd like my error class be available to every other class I create so I can display and log errors as needed. Any suggestions or links to point me where I'd like to go?

i need help trying to get this delete feature to work its not deleting from the database (by the way i took out my database names and passwords at the top of the file)

is it possible someone could help me, ive been working on this for like a week and cant figure out the problem. thanks! you can email me at spr_spng@yahoo.com


picture 2.png is showing what it looks like




Code: [Select]
<?php
$host="localhost"; // Host name
$username="username"; // Mysql username
$password="password"; // Mysql password
$db_name="database_name"; // Database name
$tbl_name="table_name"; // Table name

// Connect to server and select databse.
mysql_connect("$host", "$username", "$password")or die("cannot connect");
mysql_select_db("$db_name")or die("cannot select DB");

$sql="SELECT * FROM $tbl_name";
$result=mysql_query($sql);

$count=mysql_num_rows($result);


?>
<style>
/*table affects look of the whole table look */
table {
margin-left: auto;
margin-right: auto;
border: 1px solid #330000;
border-collapse:collapse;
width:70%;

border-width: 5px 5px 5px 5px;
border-spacing: 1px;
border-style: outset outset outset outset;
border-color: #330000 #330000 #330000 #330000;
border-collapse: separate;
background-color: #330000;


#800517

f535aa

#330000 school color
#9A0000 school color2
#991B1E school color3
#CCCC99 school color4
#9A0000

}
/*th is table header */
th {
text-align: left;
height: 2.5em;
background-color: #330000;
color: #FC0;
font-size:1.5em;
}
/*td is table data or the cells below the header*/
td {
text-align: left;
height:1.0em;
font-size:1.0em;
vertical-align:bottom;
padding:10px;

border-width: 5px 5px 5px 5px;
padding: 8px 8px 8px 8px;
border-style: outset outset outset outset;
border-color: #9A0000 #9A0000 #9A0000 #9A0000;
background-color: #CCCC99;
-moz-border-radius: 0px 0px 0px 0px;

}
</style>
<table width="400" border="0" cellspacing="1" cellpadding="0">
<tr>
<td><form name="form1" method="post" action="">
<table width="400" border="0" cellpadding="3" cellspacing="1" bgcolor="#CCCCCC">
<tr>
<td bgcolor="#FFFFFF">&nbsp;</td>
<td colspan="4" bgcolor="#FFFFFF"><strong>Pick Which Rows you want to delete, Then press delete.</strong> </td>
</tr>
<tr>
<td align="center" bgcolor="#FFFFFF"><strong>Id</strong></td>
<td align="center" bgcolor="#FFFFFF"><strong>Name</strong></td>
<td align="center" bgcolor="#FFFFFF"><strong>Lastname</strong></td>
<td align="center" bgcolor="#FFFFFF"><strong>Email</strong></td>
<td align="center" bgcolor="#FFFFFF">delete</td></tr>
<?php
while($rows=mysql_fetch_array($result)){
?>
<tr>
<td bgcolor="#FFFFFF"><? echo $rows['id']; ?></td>
<td bgcolor="#FFFFFF"><? echo $rows['name']; ?></td>
<td bgcolor="#FFFFFF"><? echo $rows['lastname']; ?></td>
<td bgcolor="#FFFFFF"><? echo $rows['email']; ?></td>
<td align="center" bgcolor="#FFFFFF"><input name="checkbox[]" type="checkbox" id="checkbox[]" value="<? echo $rows['id']; ?>"></td>
</tr>
<?php
}
?>
<tr>
<td colspan="5" align="center" bgcolor="#FFFFFF"><input name="delete" type="submit" id="delete" value="Delete"></td>
</tr>
<?
// Check if delete button active, start this // edited
if($delete){
for($i=0;$i<$count;$i++){
$del_id = $checkbox[$i];
$sql = "DELETE FROM $tbl_name WHERE id='$del_id'";
$result = mysql_query($sql);
}

// if successful redirect to delete_multiple.php
if($result){
echo "<meta http-equiv=\"refresh\" content=\"0;URL=delete_multiple.php\">";
}
}
mysql_close();
?>
</table>
</form>
</td>
</tr>
</table>

Take the following example:


<?php
class a {
var $things;
public function __construct($stuff) {
$this->things = $stuff;
}
}
class b {
var $morethings;
$this->morethings = "something";
}

$c = new a(new b);

echo $c->things->__PARENT__;
?>


The line "echo $c->things->__PARENT__;" (as you can probably imagine) does not work. How would I output what the 'b' object is stored in ('a')?

If I have defined an instance of a class in one script how do I then use this same instance and the same variable in other scripts?  For example say I have this code in a file called "index.php"


include("myclass.class.php");

$myclass = new myClass;

$myclass->$variable = "hello world";


However if I then have this code in a file called "page1.php" when I try to access the same variable it is empty. 


include("myclass.class.php");

echo($myclass->$variable)


How can I use the same instance of this class across all files keep the variable values the same?

Thanks for any help. 

Hi, I want to build a simple calculator class and one of the function is to calculate the factorial, but for some reason I cannot get this to work.

Here is class:
=========
Code: [Select]
<?php
class Calculator {

 function factorial($n) {
  if($n==1)
return 1;
  else 
return factorial($n-1)*$n;
 }
}//END CLASS Calculator

$calculator=new Calculator();
print $calculator->factorial(3);
?> 

But it doesn't work, I know this is simple but I am a little rusty with object oriented programming.

I'd appreciated any help!

Hello All,

I am fairly new to PHP class development, and I was wondering if it is normal behaviour to see classes not being able to access global variables related to PHP-based requests ($_GET, $_SESSION, etc.)? I seem to either have to use "global <var>" inside of the class to access the data, or I am forced to change the methods so then such required data is passed in as parameters. Perhaps I am just doing something wrong?

Here is an example of what I mean:

class Something
{
       function aFunc()
       {
               if (isset($_SESSION['somedata'])) { return false; } // this always returns false whether I had set the value or not
       }
       function bFunc()
       {
              global $_SESSION; // figured this would already be in a global accessible scope
              if (isset($_SESSION['somedata'])) { return false; } // now this will return false only when the value is set
       }
}


Now the above example is commented to demonstrate what I was meaning above, and I was wondering if this was the 'norm' when developing classes for PHP (and thus such values should be passed as parameters)?

Thanks!

Hi there,    This might a newbie question but I need help understanding PHP classes which am currently learning.    I have an index page.    With this three included files.    database.php config.php account.php    on database.php, the class is declared using $connection new Database(...), on this page is also all the coding for this class.   In config.php is a declared class of $account new Account($user_id);   and on account.php is all the details for the account class.    on the index.php is echo $account->sayHello;    However, My page is throwing out an error because I'm trying to use $connection->query(..) in my account.php / Account class.    I have tried to extend the Account class with Database but still have no luck.    How can I make sure the I can use a class function from another page in my Account class?        Thanks for reading

I have just start using PHP classes and was wondering how you continue an instance of a class in another file.  For example I have a folder called "includes" where I includes files that I send data to when I perform ajax request.  However how do I continue an instance of class in these files?  Hope that makes sense. 

Thanks for any help. 

Hello,

maybe back to basics, but

  [PHP] pobierz, plaintext