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PHP

Posted by Ashish Mehra
Ashish Mehra
Courses Plus Student 340 Points

is it necessary to assign value to null in function

function category_generate_Catalog($section,$limit = null, $offset = 0){
       include("connection.php");
       $section = strtolower($section);
       try{
       $sql = "Select media_id,title,category,img 
              FROM media
              WHERE LOWER(category) = ?
                ORDER BY REPLACE(
                    REPLACE(
                        REPLACE(title,'The ',''),
                        'An ',''
                    ),
                   'A ',''
                )";
        if(is_integer($limit)){
           $result = $db->prepare($sql."LIMIT ? OFFSET ?");  
           $result->bindParam(1,$section,PDO::PARAM_STR);
           $result->bindParam(2,$limit,PDO::PARAM_INT);
           $result->bindParam(3,$offset,PDO::PARAM_INT); 
        }else{
           $result = $db->prepare($sql);
           $result->bindParam(1,$section,PDO::PARAM_STR);
        }       
        $result->execute();

  }catch(Exception $e){
    echo "Unable to Retreived Result";
    echo $e->getMessage();
    exit;
  }
  $catalog = $result->fetchAll(PDO::FETCH_ASSOC);
  return $catalog;
}

1 Answer

Simon Woodard
Simon Woodard
6,545 Points
Simon Woodard
Simon Woodard
6,545 Points

It is necessary to give all function arguments a default value (like $limit = null) if your not planning on assigning them every time you execute the function.

Assigning default values for your function arguments works well as a standard, and will allow for cleaner code within your project.

For instance: if you execute your function 50 times throughout your project, but only 10 of them require the $limit argument to be specifically supplied, then you won't have to manually supply a NULL value for the other 40.

eg.

// We don't need to supply the other two arguments if they are not necessary.
category_generate_Catalog('some section'); 

// If they don't have a default value, then we do need to supply them every time.
category_generate_Catalog('some section', NULL, 0);