public bool doesWebElementExist(string linkexist)
{
     try
     {
        driver.FindElement(By.XPath(linkexist));
        return true;
     }
     catch (NoSuchElementException e)
     {
        return false;
     }
}

受Loudenvier的解决方案的启发，这里有一个扩展方法，它适用于所有ISearchContext对象，而不仅仅是IWebDriver，后者是前者的专门化。此方法还支持等待，直到元素显示出来。

static class WebDriverExtensions
{
    /// <summary>
    /// Find an element, waiting until a timeout is reached if necessary.
    /// </summary>
    /// <param name="context">The search context.</param>
    /// <param name="by">Method to find elements.</param>
    /// <param name="timeout">How many seconds to wait.</param>
    /// <param name="displayed">Require the element to be displayed?</param>
    /// <returns>The found element.</returns>
    public static IWebElement FindElement(this ISearchContext context, By by, uint timeout, bool displayed=false)
    {
        var wait = new DefaultWait<ISearchContext>(context);
        wait.Timeout = TimeSpan.FromSeconds(timeout);
        wait.IgnoreExceptionTypes(typeof(NoSuchElementException));
        return wait.Until(ctx => {
            var elem = ctx.FindElement(by);
            if (displayed && !elem.Displayed)
                return null;

            return elem;
        });
    }
}

使用示例:

var driver = new FirefoxDriver();
driver.Navigate().GoToUrl("http://localhost");
var main = driver.FindElement(By.Id("main"));
var btn = main.FindElement(By.Id("button"));
btn.Click();
var dialog = main.FindElement(By.Id("dialog"), 5, displayed: true);
Assert.AreEqual("My Dialog", dialog.Text);
driver.Close();

Python:

from selenium import webdriver
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.common.by import By

driver.find_element_by_id('someId').click()

WebDriverWait(driver, timeout).until(EC.presence_of_element_located((By.ID, 'someAnotherId'))

从EC(导入expected_conditions)中，您还可以选择其他条件。 试试这个:预期条件支持

使用Rn222的答案和akns1的答案来使用ISearchContext，返回单个元素或列表。并且可以指定元素的最小数量:

public static class SearchContextExtensions
{
    /// <summary>
    ///     Method that finds an element based on the search parameters within a specified timeout.
    /// </summary>
    /// <param name="context">The context where this is searched. Required for extension methods</param>
    /// <param name="by">The search parameters that are used to identify the element</param>
    /// <param name="timeOutInSeconds">The time that the tool should wait before throwing an exception</param>
    /// <returns> The first element found that matches the condition specified</returns>
    public static IWebElement FindElement(this ISearchContext context, By by, uint timeOutInSeconds)
    {
        if (timeOutInSeconds > 0)
        {
            var wait = new DefaultWait<ISearchContext>(context);
            wait.Timeout = TimeSpan.FromSeconds(timeOutInSeconds);
            return wait.Until<IWebElement>(ctx => ctx.FindElement(by));
        }
        return context.FindElement(by);
    }
    /// <summary>
    ///     Method that finds a list of elements based on the search parameters within a specified timeout.
    /// </summary>
    /// <param name="context">The context where this is searched. Required for extension methods</param>
    /// <param name="by">The search parameters that are used to identify the element</param>
    /// <param name="timeoutInSeconds">The time that the tool should wait before throwing an exception</param>
    /// <returns>A list of all the web elements that match the condition specified</returns>
    public static IReadOnlyCollection<IWebElement> FindElements(this ISearchContext context, By by, uint timeoutInSeconds)
    {

        if (timeoutInSeconds > 0)
        {
            var wait = new DefaultWait<ISearchContext>(context);
            wait.Timeout = TimeSpan.FromSeconds(timeoutInSeconds);
            return wait.Until<IReadOnlyCollection<IWebElement>>(ctx => ctx.FindElements(by));
        }
        return context.FindElements(by);
    }
    /// <summary>
    ///     Method that finds a list of elements with the minimum amount specified based on the search parameters within a specified timeout.<br/>
    /// </summary>
    /// <param name="context">The context where this is searched. Required for extension methods</param>
    /// <param name="by">The search parameters that are used to identify the element</param>
    /// <param name="timeoutInSeconds">The time that the tool should wait before throwing an exception</param>
    /// <param name="minNumberOfElements">
    ///     The minimum number of elements that should meet the criteria before returning the list <para/>
    ///     If this number is not met, an exception will be thrown and no elements will be returned
    ///     even if some did meet the criteria
    /// </param>
    /// <returns>A list of all the web elements that match the condition specified</returns>
    public static IReadOnlyCollection<IWebElement> FindElements(this ISearchContext context, By by, uint timeoutInSeconds, int minNumberOfElements)
    {
        var wait = new DefaultWait<ISearchContext>(context);
        if (timeoutInSeconds > 0)
        {
            wait.Timeout = TimeSpan.FromSeconds(timeoutInSeconds);
        }

        // Wait until the current context found the minimum number of elements. If not found after timeout, an exception is thrown
        wait.Until<bool>(ctx => ctx.FindElements(by).Count >= minNumberOfElements);

        // If the elements were successfuly found, just return the list
        return context.FindElements(by);
    }

}

使用示例:

var driver = new FirefoxDriver();
driver.Navigate().GoToUrl("http://localhost");
var main = driver.FindElement(By.Id("main"));
// It can be now used to wait when using elements to search
var btn = main.FindElement(By.Id("button"), 10);
btn.Click();
// This will wait up to 10 seconds until a button is found
var button = driver.FindElement(By.TagName("button"), 10)
// This will wait up to 10 seconds until a button is found, and return all the buttons found
var buttonList = driver.FindElements(By.TagName("button"), 10)
// This will wait for 10 seconds until we find at least 5 buttons
var buttonsMin = driver.FindElements(By.TagName("button"), 10, 5);
driver.Close();

我混淆了匿名函数和谓词。这里有一个小帮手方法:

   WebDriverWait wait;
    private void waitForById(string id)
    {
        if (wait == null)
            wait = new WebDriverWait(driver, new TimeSpan(0, 0, 5));

        //wait.Until(driver);
        wait.Until(d => d.FindElement(By.Id(id)));
    }

你可以在c#中找到类似的东西。

这是我在JUnit - Selenium中使用的

WebDriverWait wait = new WebDriverWait(driver, 100);
WebElement element = wait.until(ExpectedConditions.elementToBeClickable(By.id("submit")));

导入相关的包。