PHP字符串连接 - 文本消失

Question

I'm getting some apparently strange behaviour* while trying to concatenate strings in PHP.

I've pared down the following code to show where the problem lies:

class htmlElement
{
    private $tagName;
    public function __construct($tagName)
    {
        $this->setTagName($tagName);
    }
    public function setTagName($tagName)
    {
        $this->tagName = is_string($tagName) ? $tagName : NULL;
    }
    public function getTagName()
    {
        return (string)$this->tagName;
    }
    public function getHtml()
    {
        $tagName = $this->getTagName();
        $html = "<" . $tagName . "></" . $tagName . ">";
        return $html;
    }
}
$div = new htmlElement("div");
var_dump($div->getHtml());

The result of the var dump is:

string(11) "
"

The length (11) seems to be correct, but where is the text?!

*I assume it's not actually strange behaviour, and that I'm missing something really obvious!

Answer 1

Behavior is not strange, text does have <div></div> inside it. But as you print it in web/mobile browser it renders as HTML instead of plain text.

Demo: https://eval.in/600675