Selenium WebDriver从:: before伪元素的CSS属性“content”获取文本

我正在尝试验证文本“提供的信息无效或不完整”.在 Java中使用SELEnium / WebDriver显示.

我有以下HTML：

<div id="validationError">
    <ul>
        <li>required: Server Name</li>
        <li>required: Receiving Port</li>
    </ul>
</div>

使用以下CSS代码：

#validationError:before {
    content: 'The information provided is either invalid or incomplete.';
}

这是我目前的java代码：

WebElement errorBox = browser.findElement(By.id("validationError"));
Assert.assertNotNull("Could not find validation errors",errorBoX);

System.out.println("Error Explanation: " + error.getCssvalue("content") + "\n");

List<WebElement> errorList = errorBox.findElements(By.tagName("li"));
for (WebElement error : errorList) {
    System.out.println("Error: " + error.getText());
}

System.out.println("\nError Full Text: " + errorBox.getText());

这是我输出的上述代码：

Error Explanation:

Error: required: Server Name
Error: required: Receiving Port

Error Full Text: required: Server Name
required: Receiving Port

我似乎无法找到验证文本的方法“提供的信息无效或不完整.”被展示.在web元素上调用getText()也不会返回预期的字符串,但会在该div中显示任何其他普通文本.有任何想法吗？

String script = "return window.getComputedStyle(document.querySELEctor('#validationError'),':before').getPropertyValue('content')";
JavascriptExecutor js = (JavascriptExecutor)driver;
String content = (String) js.executeScript(script);
System.out.println(content);

The information provided is either invalid or incomplete.