PHP question, OOP select class

[dbdg]

Messing with classes in PHP 4, very new to OOP, anyway I have created the following select class but for some reason I have to manually add the query to the constructor other wise it doesn't work.

// Select Field (Drop Down)
class form_select_menu {
    // Properties
    var $name; // Name
    var $cssclass; // Css Style
    var $query; // sql query
    var $opvalue; // db field
    var $opname; // db field
   // Constructor
   function form_select_menu() {
      $this->query = "SELECT ID, Name FROM tblartists ORDER BY Name ASC LIMIT 10";
      $this->rQuery = mysql_query($this->query) or die(mysql_error());
      $this->row_rQuery = mysql_fetch_assoc($this->rQuery);
    }
   // Output
   function display() {
      echo "<select name=\"" . $this->name . "\" class=\"" . $this->cssclass . "\">\n";
       do {
           echo "<option value=\"" . $this->row_rQuery[$this->opvalue] . "\">" . $this->row_rQuery[$this->opname] . "</option>\n";
        } while ($this->row_rQuery = mysql_fetch_assoc($this->rQuery));
        echo "</select>\n";
    }
} 

$this->query = "SELECT ID, Name FROM tblartists ORDER BY Name ASC LIMIT 10"; is the line that is causing problems as I don't see why I should have to pass it (sort of defeats the point), if I don't include it I get query empty.

[TnT]

Maybe I'm dense, but I'm not understanding your problem. You don't know why you need to have the $this->query line in the constructor?

[dbdg]

No, I know I need $this->$query in the constructor but later in the page when I define a new class I do set it (shown below). The thing is that in the class defintion I shouldn't have to re add the sql, won't work for different queries.

$form_select_menu = new form_select_menu;
$form_select_menu->query = "SELECT ID, Name FROM tblartists ORDER BY Name ASC LIMIT 10";
$form_select_menu->display();

If I use the following, without the constructor it works fine.

class form_select {
    // Properties
    var $name; // Name
    var $cssclass; // Css Style
    var $query; // sql query
    var $opvalue; // db field
    var $opname; // db field

   function display() {
      $this->rQuery = mysql_query($this->query) or die(mysql_error());
      $this->row_rQuery = mysql_fetch_assoc($this->rQuery);
      echo "<select name=\"" . $this->name . "\" class=\"" . $this->cssclass . "\">\n";
       do {
           echo "<option value=\"" . $this->row_rQuery[$this->opvalue] . "\">" . $this->row_rQuery[$this->opname] . "</option>\n";
        } while ($this->row_rQuery = mysql_fetch_assoc($this->rQuery));
        echo "</select>\n";
    }
}