lib/classes/Swift/Mime/SimpleMimeEntity.php
public function setId($id)
    {
        if (!$this->setHeaderFieldModel($this->getIdField(), $id)) {
            $this->headers->addIdHeader($this->getIdField(), $id);
        }
        $this->id = $id;

        return $this;
    }
public function setId($id)
    {
        if (!$this->setHeaderFieldModel($this->getIdField(), $id)) {
            $this->headers->addIdHeader($this->getIdField(), $id);
        }
        $this->id = $id;

        return $this;
    }
public function setId ( $ id ) { if ( ! $ this -> setHeaderFieldModel ( $ this -> getIdField ( ) , $ id ) ) { $ this -> headers -> addIdHeader ( $ this -> getIdField ( ) , $ id ) ; } $ this -> id = $ id ; return $ this ; }
Set the CID of this entity.

@param string $id

@return $this
Set the CID of this entity .