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

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

你也可以使用

ExpectedConditions。ElementExists

你会搜索这样的元素可用性

new WebDriverWait(driver, TimeSpan.FromSeconds(timeOut)).Until(ExpectedConditions.ElementExists((By.Id(login))));

源

下面是Loudenvier解决方案的一个变体，它也适用于获得多个元素:

public static class WebDriverExtensions
{
    public static IWebElement FindElement(this IWebDriver driver, By by, int timeoutInSeconds)
    {
        if (timeoutInSeconds > 0)
        {
            var wait = new WebDriverWait(driver, TimeSpan.FromSeconds(timeoutInSeconds));
            return wait.Until(drv => drv.FindElement(by));
        }
        return driver.FindElement(by);
    }

    public static ReadOnlyCollection<IWebElement> FindElements(this IWebDriver driver, By by, int timeoutInSeconds)
    {
        if (timeoutInSeconds > 0)
        {
            var wait = new WebDriverWait(driver, TimeSpan.FromSeconds(timeoutInSeconds));
            return wait.Until(drv => (drv.FindElements(by).Count > 0) ? drv.FindElements(by) : null);
        }
        return driver.FindElements(by);
    }
}

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)));
    }

您不希望在元素更改之前等待太长时间。在这段代码中，webdriver在继续之前最多等待2秒。

WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromMilliseconds(2000));
wait.Until(ExpectedConditions.VisibilityOfAllElementsLocatedBy(By.Name("html-name")));