Using quotes in PHP statements

thehenryfam · August 31st, 2003, 12:49 AM

Hello, all. I'm presently in chapter 8 of the book. Overall, I haven't run into too much difficulty, except I must admit that having to alter many of the examples because of the register_globals=off has been very challenging considering this book is my first taste of PHP. In any event, I'm determined to stick with it and not give into the temptation of turning the setting on, especially given the security implications.

I just got the font cookie program (pages 282-284) working finally. There is one thing I have been struggling with through the last several programs, though, and I have gut feeling there is a better way to do this. It's the quoting. I know you can escape the quotes with \" to force them to appear, but take this snippet of code from my cookie_test.php modification, for example:

Code:

if ($_COOKIE["font"]["type"]) {
     $fontcookie = $_COOKIE["font"]["type"];
     echo "face=$fontcookie  "; }

It seems that there should be a way to get the $_COOKIE variable in the echo statement, but I can't figure out how. I've run into this with other programs. For instance, if I write:

Code:

if ($_COOKIE["font"]["type"]) echo "face=$_COOKIE[\"font\"][\"type\"]  ";

My PHP page won't even come up. I've also tried the single quotes within those array elements but also to no avail. What am I doing wrong?

Thanks for any help.

Scott Henry

richard.york · August 31st, 2003, 01:44 AM

Hi Scott,
A fine challenge! But not one without a solution. What you need is curly syntax. Its very straightforward.

if ($_COOKIE["font"]["type"]) echo "face={$_COOKIE["font"]["type"]} ";

This is talked about in detail in the PHP manual page on strings.
http://www.php.net/manual/en/language.types.string.php

PHP is able to recognize a single layer of nested array, but when you get into multidimensional arrays, that is arrays more than a single layer deep it has no mechanism for recognition beyond the first layer, that is not without the help of curly syntax. Which will tell PHP that the object inside of curly braces is to be treated as a variable.

The statement may be written in a couple of ways.
An alternate way of using curly syntax:
if ($_COOKIE["font"]["type"]) echo "face=${_COOKIE["font"]["type"]} ";

And by using the join operator:
if ($_COOKIE["font"]["type"]) echo "face=".$_COOKIE["font"]["type"]." ";

When you try to escape the quotes, this makes php want to treat the quotes as literal, I'll bet you'll find the string 'Array["font"]["type"]' in your html source code. The reason being, $_COOKIE is an array so it prints that as its value and ["font"]["type"] because what you wrote caused PHP to display the array nesting literally.

: )
Rich

:::::::::::::::::::::::::::::::::
Smiling Souls
http://www.smilingsouls.net
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richard.york · August 31st, 2003, 01:51 AM

Also to avoid an error of undefined variable under error_reporting E_ALL use this function:

if (isset($_COOKIE["font"]["type"])) echo "face={$_COOKIE["font"]["type"]} ";

Which means if this exists, execute this statement. Its more explicit than simply saying if this exists and does not contain a null value, execute this statement.

isset($variable) - checks for a variable's existence
empty($variable) - checks for null, integer zero, string zero, empty string, or boolean false value

The combination of these two allows for a much more explicit execution of code, which as you progress in your expertise will find much better than the flimsy alternative.

See also:
http://p2p.wrox.com/topic.asp?TOPIC_ID=1709

: )
Rich

:::::::::::::::::::::::::::::::::
Smiling Souls
http://www.smilingsouls.net
:::::::::::::::::::::::::::::::::

thehenryfam · September 2nd, 2003, 12:07 AM

Rich:

Thanks so much for taking the time to share such comprehensive replies! You've been very helpful. Once I get a bit more comfortable with the fundamentals of PHP, I'm going to dig into the PHP manual a little more. It is a daunting document at over 1,900 pages, and I must confess I have only glanced through it and read small portions up to this point.

In the meantime, thanks again for helping me with this particular issue.

Scott

richard.york · September 9th, 2003, 11:57 PM

Hey Scott,
No problem. I just wanted to point out that php.net also has downloadable versions of the manual. Which I've found to be helpful. IMO the windows help file .chm is the best version. The only downside to downloading the documentation is that the user contributed notes are not included and obviously you are also not going to be getting updates made to it but both are easily remedied with periodic updates and visits to the site. Personally I find it helpful to have right there. Its an enormous resource for writing the PHP language.

: )
Rich

:::::::::::::::::::::::::::::::::
Smiling Souls
http://www.smilingsouls.net
:::::::::::::::::::::::::::::::::

nikolai · September 10th, 2003, 12:32 AM

Totally off the original topic:

If you use Dave's Quick Search Deskbar (and in my opinion, you SHOULD), you can search www.php.net's online manual by just typing "php <search string>". This comes in really useful when you know what a function is named but don't know the order of params, the return value, etc.

For this reason, I use the online version of the PHP manual exclusively. I tried using the CHM manual, but it was more of an inconvenience than a help.

Take care,

Nik
http://www.bigaction.org/