webdriver.py 文件源码

def find_element(self, by=By.ID, value=None):
        """
        'Private' method used by the find_element_by_* methods.

        :Usage:
            Use the corresponding find_element_by_* instead of this.

        :rtype: WebElement
        """
        if not By.is_valid(by) or not isinstance(value, str):
            raise InvalidSelectorException("Invalid locator values passed in")

        return self.execute(Command.FIND_ELEMENT,
                             {'using': by, 'value': value})['value']