code: function ReplaceInnerSrc($new) {
  		$len = $this->GetInnerLen();
  		if ($len===false) return false;
  		$this->Txt = substr_replace($this->Txt, $new, $this->pST_PosEnd + 1, $len);
  		$this->PosEnd += strlen($new) - $len;
  		$this->pET_PosBeg += strlen($new) - $len;
  	}
docs: Assume FindEndTag() is previsouly called.