system/HTTP/CURLRequest.php
public function setForm(array $params, bool $multipart = false)
	{
		if ($multipart)
		{
			$this->config['multipart'] = $params;
		}
		else
		{
			$this->config['form_params'] = $params;
		}

		return $this;
	}
public function setForm(array $params, bool $multipart = false)
	{
		if ($multipart)
		{
			$this->config['multipart'] = $params;
		}
		else
		{
			$this->config['form_params'] = $params;
		}

		return $this;
	}
Set form data to be sent.

@param array   $params
@param boolean $multipart Set TRUE if you are sending CURLFiles

@return $this