[SOLVED] If variable is empty - Ignore lines in PHP ???

[a.beam.reach]

I am wondering how to ignore lines of PHP code if the applicable variable is empty.

 

For example in the code below. . . .  if the variable $r is empty. . ..  I would like the entire line:

echo "http://www.mysite.com/images/$r/1"

to be ignored.

 

Can you tell that I am very novice!!!!  I am learning though.

 

<?

// SET GALLERY OPTIONS HERE
// -----------------------
// Set Gallery options by editing this text:
$q =$_POST['q'];
$r =$_POST['r'];


echo "http://www.mysite.com/images/$q/1"
echo "http://www.mysite.com/images/$r/1"


?>

[LazyJones]

$q =$_POST['q'];
$r =$_POST['r'];

if(!empty($q)) {
echo "http://www.mysite.com/images/$q/1";
}

if(!empty($r)) {
echo "http://www.mysite.com/images/$r/1";
}

[xenophobia]

If $_POST['q'] adn $_POST['r'] is a text box then:

 

if(trim($r) != ""){
    echo ......;
}

 

If the $_POST['r'] is an option button or checkbox then:

if(isset($_POST['q'])){

    echo .......;

}

[a.beam.reach]

Thank you LazyJones and xenophobia. . ..

 

I did not get a chance to try your suggestion xenophobia. . . . as I had already tried the suggestion of LazyJones.  It worked great!

 

I did notice the suggestions were slightly different.  Guess there is more than one way to skin a cat!

 

Thanks to you both.

 

Trevor