Need some help with array problem

[DeNasio]

Hello,

I have the following code in my script:

answer 1 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100">
answer 2 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100">
answer 3 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100">
answer 4 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100">
answer 5 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100">
......

As you can see, I'm trying to get all the aswers into an array. But, when someone leave a field unanswered, then the array will contain a "". I'm trying to filter out all of the "", and strip all slaches as well.

I'm using the following code to do this:

foreach($answer as $key => $val)
   { 
   if ($val == '') {array_pop($answer);} 
   else {$val = stripslashes($val);}
   }

But this code does not work! Any one know why?

[freakysid]

array_pop() performs a very specific task and cannot be used in the way you have tried to

Arrays in PHP are a multi-talented animal. They are not just arrays in the strict sense of what an array is in C, C++ or Java for that matter. One way in which a PHP array can be used is as a stack. A stack is a collection (a.k.a data structure) that behaves in a very specific manner - you add elements to the top of the stack (known as pushing onto the stack) and remove elements from the top of the stack (known as popping elements). Think of a stack as a pile of dinner plates. You can only push a dinner plate onto the stack by placing it at the top of the stack. When you want to remove a dinner plate from the stack your only choice is to pop a plate from the top. Thus the first plate inserted into the stack will always be the last one popped out. This behaviour is fundamental to how computer programs work at a very low level (beyond my feable knowledge).

Anyway, that doesn't directly answer your question The only way I can think of doing what you want is to loop through the array as you do using foreach and copy the value accross to a new array IF it meets your conditions

foreach($answer as $anAnswer) {
   if ( $anAnswer != '' ) {
      $AnswerCopy[] = $anAnswer;
   }
} 

[Skunk]

I'm quite surprised PHP doesn't have an array function for removing the specified elemtn (or all occurences of it) from an array - it's got array functions for virtually everything else

http://www.php.net/manual/en/ref.array.php

[freddydoesphp]

My mistake DeNasio, if you want to preserve the array for later use after taking out the blank elements you will need to do as sid said and build a new array out of the non-blank elements. If all you were doing was printing them to the screen then this would have worked fine.

<?
if ($submit) {
    if(count($answer) > 0) {
        foreach($answer as $key => $val) {
            if($val != "") {
                $answer[$key] = addslashes($val);
                }
            else {
                unset($answer[$key]);
                }
            }
        reset($answer);
        foreach($answer as $key => $val) {
            print "$key = $val<br>";
            }
        }
    else {
        print "No answers submitted";
        }
    }
?>
<form action="<?=$PHP_SELF?>" method="post">
answer 1 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 2 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 3 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 4 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 5 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
<input type="submit" name="submit" value="Submit">
</form>

But you can make a simple adjustment easily like this:

<?
if ($submit) {
    if(count($answer) > 0) {
        foreach($answer as $key => $val) {
            if($val != "") {
                $newAnswer[] = addslashes($val);
                }
            else {
                continue;
                }
            }
        foreach($newAnswer as $key => $val) {
            print "$key = $val<br>";
            }
        }
    else {
        print "No answers submitted";
        }
    }
?>
<form action="<?=$PHP_SELF?>" method="post">
answer 1 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 2 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 3 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 4 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
answer 5 <INPUT TYPE="text" NAME="answer[]" VALUE="" SIZE="30" MAXLENGTH="100"><br>
<input type="submit" name="submit" value="Submit">
</form>