PHP - Need Help Understanding The Scope Of Variables

I know this is a simple question, but it's been bugging the hell out of me.

i am being told that i have an undefined variable - errorString - in a function, even though it *clearly* is defined w/i the scope of the function.  Can somebody please help me out?

Code: [Select]
[Undefined variable: errorString/code]



[php]

/**
* is fed a string email address and processes it to make sure that we're within limits:
*
*  1) must not be empty
*  2) must not be above 50 characters
*  3) must be in name@example.tld format
*
*  returns TRUE if email is valid, string (with reasons for failure) if the email is not valid
*
* @param string $email
* @return boolean|string
*/
public static function data_validateEmail($email){
// set up temporary vaiable
$errorString;

// check to see if the user's email is a null string
if (empty($email)){

$errorString .="You must supply an email address. ";

}

// then check to see if its under 50 characters

if(strlen($email) > 50){

$errorString .= "The email address can be no longer than 50 characters. ";

}

// then make sure it's in teh correct format
if (!preg_match('/^[A-Z0-9._%-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i', $email)) {

$errorString .= "The email address must be in the name@domain.tld format. ";

}



// if we've got a valid email, return true... else, we return a string error
if(empty($errorString)){

return true;

} else {

return $errorString;

}

}
[/php]


errorString is defined at the beginning of the function, so why am i told that it is undefined when, say, the length test fails?  I know this has to be a simple solution, but ive spent almost 2 hours looking at it trying to figure it out, and have gotten nowhere.... :(

and yes, part of that 2 hours was searching google for information about how PHP does variable scope in functions with multiple if statements... and all i could find was that as long as the variable is defined in the function scope, it should be available within the successive if statements.


Thanks for reading!

I have some questions about the scope of navigation :

if i define a constant like define('constant'), php manuel says it's global,

does this mean that i can use of different files also? like, i defined in define.php and used in anotherfile.php, or shoud the latter file be included then?

what about file

a.php includes file b.php which in turn includes file c.php. Can functions of a use variables of file c?

ultimately:

what about variables that are declared global inside a function but this variables is not initialized in that script, like in wordpress:

function date_i18n( $dateformatstring, $unixtimestamp = false, $gmt = false ) {
   global $wp_locale;

// more code

}

$wp_locale can be initialized in another script file?

thanks in advance

Hello all,

I have a 14 column csv that I load into an array, retrieving only the required fields, load the array into columns and perform a sort:
Code: [Select]
foreach ($array as $key => $row) {
$firstname[$key] = $row["firstn"];
    $lastname[$key] = $row["lastn"];
    $address1[$key] = $row["addr1"];
    $address2[$key] = $row["addr2"];
    $address3[$key] = $row["addr3"];
$city[$key] = $row["cit"];
$stateprov[$key] = $row["state"];
$country[$key] = $row["cntry"];
$membernumber[$key] = $row["num"];}
array_multisort($membernumber,$lastname,$firstname,$address1,$address2,$address3,$city,$stateprov,$country,$array);When I pass say the first three letters of a last name ($find = "smi"), all records matching the search criteria are returned:
Code: [Select]
foreach ($array as $key => $row) {
if (strncasecmp($find, $lastname[$key], strlen($find)) == 0) {
echo "<tr><td>" . $firstname[$key] . "</td>";
echo "<td>" . $lastname[$key] . "</td>";
echo "<td>" . $address1[$key] . "</td>";
echo "<td>" . $address2[$key] . "</td>";
echo "<td>" . $address3[$key] . "</td>";
echo "<td>" . $city[$key] . "</td>";
echo "<td>" . $stateprov[$key] . "</td>";
echo "<td>" . $country[$key] . "</td>";
echo "<td>" . $membernumber[$key] . "</td></tr>" . chr(13);
}}}So far so good. However, I'd like to put the search part into a function so I can call it a number of times without having to reload the entire csv:
Code: [Select]
function FindMember() {
foreach ($array as $key => $row) {
if (strncasecmp($find, $membernumber[$key], strlen($find)) == 0) {
echo "<tr><td>" . $firstname[$key] . "</td>";
echo "<td>" . $lastname[$key] . "</td>";
echo "<td>" . $address1[$key] . "</td>";
echo "<td>" . $address2[$key] . "</td>";
echo "<td>" . $address3[$key] . "</td>";
echo "<td>" . $city[$key] . "</td>";
echo "<td>" . $stateprov[$key] . "</td>";
echo "<td>" . $country[$key] . "</td>";
echo "<td align='right'>" . $membernumber[$key] . "</td></tr>" . chr(13);
}}}}The search criteria would come from a second txt file with every line containing 2 numbers, separated by a comma:
Code: [Select]
foreach ($lines as $member => $numbers) {
$exploded = explode(",", $numbers);
$find = $exploded[1];
FindMember();here $exploded[1] corresponds to $membernumber[$key], so this is where I would call the function, but this is where I run into trouble, nothing gets returned.

Does this have something to do with the scope of variables inside a user-defined function?

I'd appreciate it if someone could point me in the right direction.

TIA

Hi Guys   I have a question about maintaining scope in OOP.  I may just be going about it in completely the wrong way but I'm here to learn.   Lets say I have a base class called 'first; set out as per the code below.    In the first class there is a method that instantiates another class - called second. This second class extends the first class and I want it to be able to set errors on the first class.  The only way I can maintain it's scope is to pass $this into the constructor of the second class.   My questions a   1) Is this the right way to maintain scope? 2) Would this be bad practice and I should explore a different model for setting out these classes? 3) Would it be considered better practice to make $errors a static property?     Keen to do things the right way so any advice is very welcome

class first {

	public $errors = array();
	
	public function __construct(){
		
		$this->callSecondClass();
		$this->render();
		
	}
	
	public function callSecondClass(){
		
		$t = new second($this);
		
	}

	public function render(){
	
		echo "I am rendering errors:";
		print_r($this->errors);
	}

}

class second extends first {

	
	public function __construct($obj){
			
		$obj->errors[] = 'ERROR FROM SECOND CLASS';
	}

}
 

Edited by Drongo_III, 14 August 2014 - 04:54 PM.

i have a text box, the no of text boxes that are displayed are random depending upon the condition of the loop..
hosting[] takes up many no of values
<input type='text' name='hosting[]' size='2' /> when the form is submitted
i use the following code to access the content of hosting[]

$link_no = $_POST['hosting'];
$total_actual_links = null;
foreach($link_no as $total_link)
{
$total_actual_links[] = $total_link;

}

now i get the results in $total_actual_links[].. i want to pass the value of this array into the value of another text box of other form which i get on submission of the 1st form..
i do not knw how shud i do this.. please help