關鍵程式碼：

        //切換frame
        driver.switchTo ( ).frame ( "i" );

        //根據元素定位找到select標籤
        Select level = new Select ( driver.findElement ( By.tagName ( "select" ) ) );
        
        //getOptions() 方法獲得WebElement集合
        List <WebElement> webElements = level.getOptions ( );

        //新建一個List，用來儲存每個選項的文字值
        List <String> downs = new ArrayList <String> ( );

        for (WebElement webElement : webElements) {
            System.out.println ( "下拉框選項的值：" + webElement.getText ( ) );
            downs.add ( webElement.getText ( ) );
        }
 

全部程式碼

public class select {

    public static void main(String[] args) throws InterruptedException {

        System.setProperty ( "webdriver.chrome.driver", "D:\\driver\\chromedriver.exe" );
        WebDriver driver = new ChromeDriver ( );
        driver.manage ( ).window ( ).maximize ( );
        driver.get ( "http://www.w3school.com.cn/tiy/t.asp?f=html_select" );

        //切換frame
        driver.switchTo ( ).frame ( "i" );

        //根據元素定位找到select標籤
        Select level = new Select ( driver.findElement ( By.tagName ( "select" ) ) );

        //getOptions() 方法獲得WebElement集合
        List <WebElement> webElements = level.getOptions ( );

        //新建一個List，用來儲存每個選項的文字值
        List <String> downs = new ArrayList <String> ( );

        for (WebElement webElement : webElements) {
            System.out.println ( "下拉框選項的值：" + webElement.getText ( ) );
            downs.add ( webElement.getText ( ) );
        }
        
        driver.quit ( );
    }
}