Joining two Variable together

LuckyLucy

I am trying to break, I mean mod some current code to add some extra features.

Here is the current function that I need to try and change, it is a custom function used in a phpbb modification to allow you to pull in a wordpress post in to your forum.


function wpu_do_crosspost($postID, $post, $future=false) {
   global $wpSettings, $phpbbForum, $phpbb_root_path, $phpEx, $db, $auth;
   $forum_id = false;
   $found_future_xpost = false;
   if ( (isset($_POST['sel_wpuxpost'])) && (isset($_POST['chk_wpuxpost'])) ) {
      $forum_id = (int)$_POST['sel_wpuxpost'];
   } else if ( $wpSettings['xpostforce'] > -1 ) {
      $forum_id = $wpSettings['xpostforce'];
   } else if($future) {
      $phpbbForum->leave();
      $forum_id = get_post_meta($postID, '_wpu_future_xpost', true);
      if ($forum_id === '')  {
         $forum_id = false;
      } else {
         $forum_id = (int)$forum_id;
         delete_post_meta($postID, '_wpu_future_xpost');
      }
      $phpbbForum->enter();
   }

Now the only important thing here is $post Variable and this is the value I want to enhance.

What I want to do is add some extra data (my custom Variable $WPCustomfield in to the $post Variable.

This is what I would be trying to achieve

if $WPCustomfield not Null then $WPCustomfield + $post = $post

if (!isset($WPCustomfield)) {
$post = $post + $WPCustomfield;
}

Now I know the above two lines will not work but I am just trying to show you what I am trying to do 🙂

I am very new to PHP so any help or support on the above would be great

NogDog

In PHP the concatenation operator is the period (full stop), not the plus sign (which is the JavaScript concatenation operator).

LuckyLucy

Thank you for your reply NogDog

Sorry I was just trying to show an example but are you saying this would work ?

if (!isset($WPCustomfield)) {
$post = $post . $WPCustomfield;
}

bradgrafelman

LuckyLucy;10951116 wrote:
are you saying this would work ?
if (!isset($WPCustomfield)) {
$post = $post . $WPCustomfield;
}

That code doesn't make much sense.. you first check if a variable isn't set and, if it's not set, you.. try to use it?

NogDog

LuckyLucy;10951116 wrote:
Thank you for your reply NogDog

Sorry I was just trying to show an example but are you saying this would work ?
if (!isset($WPCustomfield)) {
$post = $post . $WPCustomfield;
}

Well, that's basically what I was saying, but I didn't look at it as closely as Brad did. 😉

LuckyLucy

what about this

if (isset($WPCustomfield)) {
$post = $post . $WPCustomfield;
}

bradgrafelman

LuckyLucy;10951148 wrote:
what about this
if (isset($WPCustomfield)) {
$post = $post . $WPCustomfield;
} 

That makes much more sense. You could also shorten it a bit, if you wanted:

if (isset($WPCustomfield))
    $post .= $WPCustomfield;

NogDog

bradgrafelman;10951150 wrote:
That makes much more sense. You could also shorten it a bit, if you wanted:
if (isset($WPCustomfield))
    $post .= $WPCustomfield;

Or...

$post .= (isset($WPCustomfield)) ? $WPCustomfield : '';

Or you could even do the following, though the purists would look down their noses at you. 😉

$post .= @ $WPCustomfield;

bradgrafelman

Or (if using PHP 5.3+)...

(!isset($WPCustomfield) ?: $post .= $WPCustomfield);

(3 characters shorter :p)

LuckyLucy

Thanks guys for all your help I am sorry I slipped up with the original isset example, I have to admit this is my very first go at coding so I am sorry if I do ask silly questions.

I was worried at first that I might be over writing the $post variable but as NogDog pointed out (thank you) . is concatenation operator.

Now I guess I have more question sorry you did all get me in to this but I am liking it.

the value for $WPCustomfield is going to be the file name of a image eg my image.jpg

To display that on any webpage I am going to have to add some html to the value. Can i do that in the same way as I do the concatenation of the php variable

$WPCustomfield = '<img src="http://www.site.com/ . $WPCustomfield " align="texttop">'

As we are dealing with html do I need to do any thing special to escape the html syntax ?.

And my last question

is isset the correct method to use yes it will return if there is a result but I am always assuming that the result would be a image if its not I am going to create a nice white image with a red X on it.

Should I be doing

if $WPCustomfield = *.jpg,jpeg,gif,png then ok print image else ignore

NogDog

Probably the simplest way is to use double quotes for the string literal to support variable interpolation within it, then use single quotes around the HTML attribute values inside the string. Then no concatenation nor escaping is needed. (And don't forget the required ALT attribute. 😉 )

$WPCustomfield = "<img src='http://www.site.com/$WPCustomfield' align='texttop' alt=''>";

LuckyLucy

Thanks again for the example if I needed to do a multiline could I also use the concatenation trick again

$WPCustomfield = "<img src='http://www.site.com/$WPCustomfield' align='texttop' alt=''>" .
"<p>&nbsp;</p>";

I am also trying to validate that $WPCustomfield is a image I was looking at a eregi example but on looking at the manual it show that its not a good idea to use it due to not being supported in php 6 is there another easy way ?

NogDog

The concatenation will work, but it will be output as a single line unless you include a newline in there, too. If you in fact want to output a newline (as opposed to outputting one line but breaking it up in the source code for programming convenience), you could simply type the newline in:

$variable = "This is line one and includes a $variable in it.
Here is line 2: see how the closing double quote is on this line?";

As far as the validation, the preg() functions are the current regular expression functions which should replace the corresponding ereg() functions. Whether it's the best choice for what you want to do, though, depends on the exact validation you want to do.