private function addHeader($name, $value)
	{
		if (!$this->hasHeader($name)) {
			return $this->setHeader($name, $value);
		}

		if (!is_array($value)) {
			$value = [$value];
		}

		foreach ($value as $element) {
			$this->headers[$this->headerNames[strtolower($name)]][] = $element;
		}

		return $this;
	}
private function addHeader($name, $value)
	{
		if (!$this->hasHeader($name)) {
			return $this->setHeader($name, $value);
		}

		if (!is_array($value)) {
			$value = [$value];
		}

		foreach ($value as $element) {
			$this->headers[$this->headerNames[strtolower($name)]][] = $element;
		}

		return $this;
	}
private function addHeader ( $ name , $ value ) { if ( ! $ this -> hasHeader ( $ name ) ) { return $ this -> setHeader ( $ name , $ value ) ; } if ( ! is_array ( $ value ) ) { $ value = [ $ value ] ; } foreach ( $ value as $ element ) { $ this -> headers [ $ this -> headerNames [ strtolower ( $ name ) ] ] [ ] = $ element ; } return $ this ; }
Add the header.

@param string $name
@param string|string[] $value
@return $this
Add the header .