PHP 8.1 var is declared in class and value to this var assigned in function but value is not availab-CodePudding

I'm trying to implement a contact form for a website running on PHP 8.1 and found some useful PHP scripts which seem to be outdated by now, though. I've refactored it as best as I can but I still get an error saying "imagecreate(): Argument #1 ($width) must be greater than 0". Here is the code

class FGCaptchaCreator extends FG_CaptchaHandler
{
    var $image;
    var $width;
    var $height;
    var $margin_y;
    var $charset;
    var $nChars;
    var $linecolor;
    var $code;
    var $show_captcha_var;
    var $nlines;
    var $enc_key;
    var $captcha_var_name;

    function FGCaptchaCreator($captcha_var_name)
    {
        $this->width = 150;
        $this->height= 60;
        $this->charset="2356789ABCDEFGHJKLMNPQRSTUVWXYZ";
        $this->nChars=6;
        $this->margin_y = 10;

        $this->nlines = 2;
        $this->font_file = 'include/SFOldRepublicSCBold.ttf';
        $this->enc_key="GhsnR5^Hyhsfg";
        $this->captcha_var_name = $captcha_var_name;
 
   }
...
}

The error is thrown in this function

function Create()
    {
        $this->image = imagecreate($this->width, $this->height);
        imagecolorallocate($this->image, 255, 255, 255);

        $this->code = $this->CreateCode();
        return true;
    }

I've tried assigning the value in the first declaration instead of in the function, but I and the captcha image displays correctly but I want to know how to do it "properly".

CodePudding user response：

You need to rename function FGCaptchaCreator($captcha_var_name) to function __construct($captcha_var_name), because since php8.0 methods named same as class are no longer considered as constructors.

Also as var is an outdated language construct I would also add visibility to each property. And if it's clear from code - type-hint properties also, e.g.:

class FGCaptchaCreator extends FG_CaptchaHandler
{
    protected $image;
    protected int $width;
    protected int $height;
    // etc

Visibility and return type-hints for methods should be added too:

public function __construct($captcha_var_name)
public function Create(): bool