用途
以下方法切换到modelframe

driver.switchTo().frame("ModelFrameTitle");

或

driver.switchTo().activeElement()

希望这个能管用

您使用的不是模型对话框，而是一个单独的窗口。
使用此代码：

private static Object firstHandle;
private static Object lastHandle;
public static void switchToWindowsPopup() {
    Set<String> handles = DriverManager.getCurrent().getWindowHandles();
    Iterator<String> itr = handles.iterator();
    firstHandle = itr.next();
    lastHandle = firstHandle;
    while (itr.hasNext()) {
        lastHandle = itr.next();
    }
    DriverManager.getCurrent().switchTo().window(lastHandle.toString());
}
public static void switchToMainWindow() {
    DriverManager.getCurrent().switchTo().window(firstHandle.toString());

Try the below code. It is working in IE but not in FF22. If找到模态对话框is printed in Console, then Modal dialog is identified and switched.

public class ModalDialog {
        public static void main(String[] args) throws InterruptedException {
            // TODO Auto-generated method stub
            WebDriver driver = new InternetExplorerDriver();
            //WebDriver driver = new FirefoxDriver();
            driver.get("http://samples.msdn.microsoft.com/workshop/samples/author/dhtml/refs/showModalDialog2.htm");
            String parent = driver.getWindowHandle();
            WebDriverWait wait = new WebDriverWait(driver, 10);
            WebElement push_to_create = wait.until(ExpectedConditions
                    .elementToBeClickable(By
                            .cssSelector("input[value='Push To Create']")));
            push_to_create.click();
            waitForWindow(driver);
            switchToModalDialog(driver, parent);
        }
        public static void waitForWindow(WebDriver driver)
                throws InterruptedException {
            //wait until number of window handles become 2 or until 6 seconds are completed.
            int timecount = 1;
            do {
                driver.getWindowHandles();
                Thread.sleep(200);
                timecount++;
                if (timecount > 30) {
                    break;
                }
            } while (driver.getWindowHandles().size() != 2);
        }
        public static void switchToModalDialog(WebDriver driver, String parent) { 
                //Switch to Modal dialog
            if (driver.getWindowHandles().size() == 2) {
                for (String window : driver.getWindowHandles()) {
                    if (!window.equals(parent)) {
                        driver.switchTo().window(window);
                        System.out.println("Modal dialog found");
                        break;
                    }
                }
            }
        }
    }

R（R selenium ）溶液：我有一个弹出对话框（这是动态生成的），因此在原始页面源代码中无法检测这里是为我工作的方法：
方法1：模拟按Tab键并切换到该模态对话框我的当前键集中在模态对话框

remDr$sendKeysToActiveElement(list(key = "tab"))
Sys.sleep(5)
remDr$sendKeysToActiveElement(list(key = "enter"))
Sys.sleep(15)

后面的下拉按钮方法2：如果你能找到框架（或iframe），将焦点移到它

date_filter_frame <- remDr$findElement(using = "tag name", 'iframe')
date_filter_frame$highlightElement()
Sys.sleep(5)
remDr$switchToFrame(date_filter_frame)
Sys.sleep(2)

现在你可以在框架中搜索元素了。记住在命令之间放置足够的Sys.sleep，以便正确加载元素（以防万一）

date_filter_element <- remDr$findElement(using = "xpath", paste0("//*[contains(text(), 'Week to Date')]"))
date_filter_element$highlightElement()

试试这个代码，包括你的对象名和变量工作.

Set<String> windowids = driver.getWindowHandles();
Iterator<String> iter= windowids.iterator();
for (int i = 1; i < sh.getRows(); i++)
{   
while(iter.hasNext())
{
System.out.println("Main Window ID :"+iter.next());
}
driver.findElement(By.id("lgnLogin_UserName")).clear();
driver.findElement(By.id("lgnLogin_UserName")).sendKeys(sh.getCell(0, 
i).getContents());
driver.findElement(By.id("lgnLogin_Password")).clear();
driver.findElement(By.id("lgnLogin_Password")).sendKeys(sh.getCell(1, 
i).getContents());
driver.findElement(By.id("lgnLogin_LoginButton")).click();
Thread.sleep(5000L);
            windowids = driver.getWindowHandles();
    iter= windowids.iterator();
    String main_windowID=iter.next();
    String tabbed_windowID=iter.next();
    System.out.println("Main Window ID :"+main_windowID);
    //switch over to pop-up window
    Thread.sleep(1000);
    driver.switchTo().window(tabbed_windowID);
    System.out.println("Pop-up window Title : "+driver.getTitle());

我试过了，对你很有效。

String mainWinHander = webDriver.getWindowHandle();
// code for clicking button to open new window is ommited
//Now the window opened. So here reture the handle with size = 2
Set<String> handles = webDriver.getWindowHandles();
for(String handle : handles)
{
    if(!mainWinHander.equals(handle))
    {
        // Here will block for ever. No exception and timeout!
        WebDriver popup = webDriver.switchTo().window(handle);
        // do something with popup
        popup.close();
    }
}

假设预期只是弹出两个窗口（一个父窗口，一个弹出窗口），那么只需等待两个窗口出现，找到另一个窗口句柄并切换到它。

WebElement link = // element that will showModalDialog()
// Click on the link, but don't wait for the document to finish
final JavascriptExecutor executor = (JavascriptExecutor) driver;
executor.executeScript(
    "var el=arguments[0]; setTimeout(function() { el.click(); }, 100);",
  link);
// wait for there to be two windows and choose the one that is 
// not the original window
final String parentWindowHandle = driver.getWindowHandle();
new WebDriverWait(driver, 60, 1000)
    .until(new Function<WebDriver, Boolean>() {
    @Override
    public Boolean apply(final WebDriver driver) {
        final String[] windowHandles =
            driver.getWindowHandles().toArray(new String[0]);
        if (windowHandles.length != 2) {
            return false;
        }
        if (windowHandles[0].equals(parentWindowHandle)) {
            driver.switchTo().window(windowHandles[1]);
        } else {
            driver.switchTo().window(windowHandles[0]);
        }
        return true;
    }
});

不，模型窗口需要由javaScriptExecutor处理，因为主要模型窗口由窗口模型组成，这将在模型出现后工作，然后控制进入模型并单击预期元素。
必须导入javascriptexector
如下所述，

Javascriptexecutor js =(Javascriptexecutor).driver;
js.executescript(**<element to be clicked>**);

pidoss. 1加上我的2美分，即使问题太老了

public void PressEnterKey()
    {
        var simulator = new InputSimulator();
        simulator.Keyboard.KeyPress(VirtualKeyCode.RETURN);
    }

你可以创建一个类似上面的方法，并在需要的地方调用它。
pidoss. 2 -你也可以改变键盘输入（如向上箭头，向下箭头，向下翻页等）