new WebDriverWait(driver, TimeSpan.FromSeconds(10)).
   Until(ExpectedConditions.PresenceOfAllElementsLocatedBy((By.Id("toast-container"))));

// Wait up to 5 seconds with no minimum for a UI element to be found
WebDriverWait wait = new WebDriverWait(_pagedriver, TimeSpan.FromSeconds(5));
IWebElement title = wait.Until<IWebElement>((d) =>
{
    return d.FindElement(By.ClassName("MainContentHeader"));
});

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

WebDriverWait将不生效。

var driver = new FirefoxDriver(
    new FirefoxOptions().PageLoadStrategy = PageLoadStrategy.Eager
);
driver.Navigate().GoToUrl("xxx");
new WebDriverWait(driver, TimeSpan.FromSeconds(60))
    .Until(d => d.FindElement(By.Id("xxx"))); // A tag that close to the end

一旦页面是“交互式的”，这将立即抛出异常。我不知道为什么，但是超时就好像它不存在一样。

也许SeleniumExtras。WaitHelpers很管用，但我没试过。这是官方的，但它被拆分为另一个NuGet包。你可以参考c# Selenium 'ExpectedConditions is obsolete'。

我使用FindElements并检查Count == 0。如果为真，则使用await Task.Delay。这真的不是很有效。

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();

你可以使用以下方法:

使用命名空间:

using SeleniumExtras.WaitHelpers;

在代码:

WebDriverWait wait = new WebDriverWait(driver, new TimeSpan(0, 0, 5));
wait.Until(ExpectedConditions.ElementExists(By.Id("login")));