Help with getting constant value from array

[ppowell]

	var $filterArray = array('reverse' => IMG_FILTER_NEGATE,
						 'edge highlight' => IMG_FILTER_EDGEDETECT,
						 'emboss' => IMG_FILTER_EMBOSS,
						 'gaussian blur' => IMG_FILTER_GAUSSIAN_BLUR,
						 'blur' => IMG_FILTER_SELECTIVE_BLUR,
					         'sketchy' => IMG_FILTER_MEAN_REMOVAL);

I am trying to generate an HTML dropdown from this array, however, when I do, the value that should go in the OPTION tag literally becomes this:

<option value="IMG_FILTER_EMBOSS">emboss</OPTION>

Which is completely wrong; I want the actual constant IMG_FILTER_EMBOSS instead, which should display as an integer within the OPTION tag.

How do I do this?

Code:

	/**
	 * Generate a filter technique dropdown HTML with any additional features to the array before display
	 * 
	 * *NOTE* This method will be called outside of the $this->image property having existence and thus will have to be used as a placeholder to self-instantiate using $this->self
	 *
	 * @access public
	 * @param array $newFilterArray (optional)
	 * @return mixed HTML
	 */
	function &generateFilterDropdown($newFilterArray = '') {			// STATIC HTML STRING METHOD
		if (!is_object($this) || @!is_a($this, 'ImageFilterTechniqueGenerator')) {
		 $self =& new ImageFilterTechniqueGenerator('placeholder');
		} else {
		 $self =& $this;											// MAKE A LOCAL REFERENCE POINTER TO KEEP CODE CONSISTENT
		}
		if (is_array($newFilterArray) && @sizeof($newFilterArray) > 0) $self->setFilterArray($newFilterArray);
		$filterArray = $self->getFilterArray();
		if (is_array($filterArray) && @sizeof($filterArray) > 0) {
		 $html = "<select multiple name=\"filter_tech[]\" size=\"";
		 $html .= (sizeof($filterArray) > 5) ? 5 : sizeof($filterArray);
		 $html .= "\">\n";
		 foreach ($filterArray as $display => $filter) {
		  print_r("filter = $filter = ${$filter}<P>"); // THIS PRODUCES "filter = IMG_FILTER_EMBOSS = 
		  $html .= " <option value=\"${$filter}\"" . $self->disp->preSelect(${$filter}, @array_search(array_values($filterArray), ${$filter})) . '>' . 
		                  str_replace('<', '&lt;', str_replace('\\', '', $display)) . "</option>\n";
		 }
		 $html .= "</select>\n";
		}

	return $html;		
}

Thanx
Phil

[madwormer2]

Are they actually defined?

Yes.

Okay, erm... well, you could just replace them with their values manually. It's not like they're gonna change, they're constants 😃

Array ( "reverse" => 0, "edge highlight" => 5, "emboss" => 6, "gaussian blur"=> 7, "blur" => 8, "sketchy" => 9 );

[jdorsch]

The problem you are having is because the constants are not defined or you are referencing them wrong.

If the constants are defined within a class then you need to do

  // outside class
  echo ClassName::MY_CONSTANT ;

  // within class
  echo self::MY_CONSTANT ;

Also, you are using some stuff wrong in your string variables

$taco = 'burrito' ;
$burrito = 10 ;

echo "Stuff : $taco" ;  // outputs 'Stuff : burrito'
echo "Stuff: ${$taco}" ; // outputs 'Stuff : 10'  ---> $$taco = $burrito = 10
echo "Stuff: \${$taco}" ; // outputs 'Stuff : $burrito' ;

define( 'MY_CONSTANT', 20 ) ;
$stuff = MY_CONSTANT ;

echo "$stuff" // outputs 20
echo "${$stuff}" // outputs nothing because $$stuff = $20 = nada


// No if MY_CONSTANT is undefined, php just treats it like a string so

$MY_CONSTANT = 20 // This is not a constant but a capitalized variable and bad practice

$taco = MY_CONSTANT // same as saying $taco = 'MY_CONSTANT' ;
echo "$taco" // outputs MY_CONSTANT
echo "${$taco}" // outputs 20 --> $$taco = $MY_CONSTANT = 20  

[jdorsch]

madwormer2 wrote:

Are they actually defined?

Yes.

Okay, erm... well, you could just replace them with their values manually. It's not like they're gonna change, they're constants 😃

Array ( "reverse" => 0, "edge highlight" => 5, "emboss" => 6, "gaussian blur"=> 7, "blur" => 8, "sketchy" => 9 );

Thats a bad idea. The idea of a constant is that it never changes during run-time, but that it can be changed by the programmer as part of a configuration. For instance database login info, price modifiers, conversions to other currencies etc.