Please clean up your code, the styling needs to be fixed as w...

Please clean up your code, the styling needs to be fixed as well as the following:

if(in_array($this->ext,array("jpg","gif","png","bmp","jpeg"))){
$type="image/$this->ext";
}

You can modify this to simply be: $this->type = mime_content_type($this->filename);

See the following:
php.net/manual/en/function.mime-con ...

Additionally, in terms of your variables, it seems that you switch between $this->variable and $variable, which while will work in your class, you may run in to issues in larger classes/projects.

Good start, though!