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Support features

针对更高层面功能的额外支持类.

Selenium的核心库试图提供底层以及普适的功能. 每种语言的支持类都为常见交互提供特定的包装器, 可用于简化某些行为.

1 - 期望状态的等待

本文档描述了一系列类, 这些类用于明确指定在测试中需要等待的各种条件.

期望状态与 显示等待 一起使用. 与其定义要使用 lambda 执行的代码块, 不如使用 lambda 执行可以创建 Conditions 方法来表示等待的常见事物. 有些方法将定位器作为参数, 有些方法将元素作为参数.

这些方法可以包括以下条件:

  • 元素存在
  • 元素已过期
  • 元素可见
  • 文本可见
  • 标题包含特定值

Expected Conditions Documentation

Add Example

    wait = WebDriverWait(driver, timeout=2)
    wait.until(EC.visibility_of_element_located((By.ID, "revealed")))
.NET stopped supporting Expected Conditions in Selenium 4 to minimize maintenance hassle and redundancy.
Ruby makes frequent use of blocks, procs and lambdas and does not need Expected Conditions classes

Add Example

Add Example

2 - 命令监听器

允许您在每次发送特定 Selenium 命令时执行自定义操作

Add Example

Add Example

Add Example

Add Example

Add Example

Add Example

3 - 同颜色一起工作

在测试中, 您偶尔会需要验证某事物的颜色；问题是网络上的颜色定义不是个常量. 如果有一种简单的方法可以比较颜色的十六进制与RGB呈现, 或者颜色的RGBA与HSLA呈现, 岂不美哉?

不用担心有一个解决方案：Color 类!

首先, 您需要导入该类:

import org.openqa.selenium.support.Color;
  
from selenium.webdriver.support.color import Color
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  
include Selenium::WebDriver::Support
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  

import org.openqa.selenium.support.Color

您现在可以开始创建颜色对象. 每个颜色对象都需要使用您颜色的字符串定义来创建. 支持的颜色定义如下:

private final Color HEX_COLOUR = Color.fromString("#2F7ED8");
private final Color RGB_COLOUR = Color.fromString("rgb(255, 255, 255)");
private final Color RGB_COLOUR = Color.fromString("rgb(40%, 20%, 40%)");
private final Color RGBA_COLOUR = Color.fromString("rgba(255, 255, 255, 0.5)");
private final Color RGBA_COLOUR = Color.fromString("rgba(40%, 20%, 40%, 0.5)");
private final Color HSL_COLOUR = Color.fromString("hsl(100, 0%, 50%)");
private final Color HSLA_COLOUR = Color.fromString("hsla(100, 0%, 50%, 0.5)");
  
HEX_COLOUR = Color.from_string('#2F7ED8')
RGB_COLOUR = Color.from_string('rgb(255, 255, 255)')
RGB_COLOUR = Color.from_string('rgb(40%, 20%, 40%)')
RGBA_COLOUR = Color.from_string('rgba(255, 255, 255, 0.5)')
RGBA_COLOUR = Color.from_string('rgba(40%, 20%, 40%, 0.5)')
HSL_COLOUR = Color.from_string('hsl(100, 0%, 50%)')
HSLA_COLOUR = Color.from_string('hsla(100, 0%, 50%, 0.5)')
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  
HEX_COLOUR = Color.from_string('#2F7ED8')
RGB_COLOUR = Color.from_string('rgb(255, 255, 255)')
RGB_COLOUR = Color.from_string('rgb(40%, 20%, 40%)')
RGBA_COLOUR = Color.from_string('rgba(255, 255, 255, 0.5)')
RGBA_COLOUR = Color.from_string('rgba(40%, 20%, 40%, 0.5)')
HSL_COLOUR = Color.from_string('hsl(100, 0%, 50%)')
HSLA_COLOUR = Color.from_string('hsla(100, 0%, 50%, 0.5)')
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  

private val HEX_COLOUR = Color.fromString("#2F7ED8")
private val RGB_COLOUR = Color.fromString("rgb(255, 255, 255)")
private val RGB_COLOUR_PERCENT = Color.fromString("rgb(40%, 20%, 40%)")
private val RGBA_COLOUR = Color.fromString("rgba(255, 255, 255, 0.5)")
private val RGBA_COLOUR_PERCENT = Color.fromString("rgba(40%, 20%, 40%, 0.5)")
private val HSL_COLOUR = Color.fromString("hsl(100, 0%, 50%)")
private val HSLA_COLOUR = Color.fromString("hsla(100, 0%, 50%, 0.5)")

Color类还支持在以下网址中指定的所有基本颜色定义 http://www.w3.org/TR/css3-color/#html4.

private final Color BLACK = Color.fromString("black");
private final Color CHOCOLATE = Color.fromString("chocolate");
private final Color HOTPINK = Color.fromString("hotpink");
  
BLACK = Color.from_string('black')
CHOCOLATE = Color.from_string('chocolate')
HOTPINK = Color.from_string('hotpink')
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  
BLACK = Color.from_string('black')
CHOCOLATE = Color.from_string('chocolate')
HOTPINK = Color.from_string('hotpink')
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  

private val BLACK = Color.fromString("black")
private val CHOCOLATE = Color.fromString("chocolate")
private val HOTPINK = Color.fromString("hotpink")

如果元素上未设置颜色, 则有时浏览器会返回“透明”的颜色值. Color类也支持此功能:

private final Color TRANSPARENT = Color.fromString("transparent");
  
TRANSPARENT = Color.from_string('transparent')
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  
TRANSPARENT = Color.from_string('transparent')
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  

private val TRANSPARENT = Color.fromString("transparent")

现在, 您可以安全地查询元素以获取其颜色/背景色, 任何响应都将被正确解析并转换为有效的Color对象:

Color loginButtonColour = Color.fromString(driver.findElement(By.id("login")).getCssValue("color"));

Color loginButtonBackgroundColour = Color.fromString(driver.findElement(By.id("login")).getCssValue("background-color"));
  
login_button_colour = Color.from_string(driver.find_element(By.ID,'login').value_of_css_property('color'))

login_button_background_colour = Color.from_string(driver.find_element(By.ID,'login').value_of_css_property('background-color'))
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  
login_button_colour = Color.from_string(driver.find_element(id: 'login').css_value('color'))

login_button_background_colour = Color.from_string(driver.find_element(id: 'login').css_value('background-color'))
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  

val loginButtonColour = Color.fromString(driver.findElement(By.id("login")).getCssValue("color"))

val loginButtonBackgroundColour = Color.fromString(driver.findElement(By.id("login")).getCssValue("background-color"))

然后, 您可以直接比较颜色对象:

assert loginButtonBackgroundColour.equals(HOTPINK);
  
assert login_button_background_colour == HOTPINK
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  
assert(login_button_background_colour == HOTPINK)
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  

assert(loginButtonBackgroundColour.equals(HOTPINK))

或者, 您可以将颜色转换为以下格式之一并执行静态验证:

assert loginButtonBackgroundColour.asHex().equals("#ff69b4");
assert loginButtonBackgroundColour.asRgba().equals("rgba(255, 105, 180, 1)");
assert loginButtonBackgroundColour.asRgb().equals("rgb(255, 105, 180)");
  
assert login_button_background_colour.hex == '#ff69b4'
assert login_button_background_colour.rgba == 'rgba(255, 105, 180, 1)'
assert login_button_background_colour.rgb == 'rgb(255, 105, 180)'
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  
assert(login_button_background_colour.hex == '#ff69b4')
assert(login_button_background_colour.rgba == 'rgba(255, 105, 180, 1)')
assert(login_button_background_colour.rgb == 'rgb(255, 105, 180)')
  
// This feature is not implemented - Help us by sending a pr to implement this feature
  

assert(loginButtonBackgroundColour.asHex().equals("#ff69b4"))
assert(loginButtonBackgroundColour.asRgba().equals("rgba(255, 105, 180, 1)"))
assert(loginButtonBackgroundColour.asRgb().equals("rgb(255, 105, 180)"))

颜色不再是问题.

4 - 线程守卫

此类仅在Java中可用

ThreadGuard检查是否仅从创建驱动程序的同一线程中调用了驱动程序. 线程问题 (尤其是在Parallel中运行测试时) 可能遇到神秘并且难以诊断错误. 使用此包装器可以防止此类错误,
并且在发生此类情况时会抛出异常.

以下的示例模拟一种线程冲突的情况:

public class DriverClash {
  //thread main (id 1) created this driver
  private WebDriver protectedDriver = ThreadGuard.protect(new ChromeDriver());

  static {
    System.setProperty("webdriver.chrome.driver", "<Set path to your Chromedriver>");
  }

  //Thread-1 (id 24) is calling the same driver causing the clash to happen
  Runnable r1 = () -> {protectedDriver.get("https://selenium.dev");};
  Thread thr1 = new Thread(r1);

  void runThreads(){
    thr1.start();
  }

  public static void main(String[] args) {
    new DriverClash().runThreads();
  }
}

结果如下所示:

Exception in thread "Thread-1" org.openqa.selenium.WebDriverException:
Thread safety error; this instance of WebDriver was constructed
on thread main (id 1)and is being accessed by thread Thread-1 (id 24)
This is not permitted and *will* cause undefined behaviour

正如示例所示:

  • protectedDriver 将在主线程中创建
  • 我们使用Java的 Runnable 启动一个新进程, 并使用一个新的 Thread 运行该进程
  • 这两个 Thread 都会发生冲突, 因为主线程的内存中没有 protectedDriver
  • ThreadGuard.protect 会抛出异常

注意:

这不能代替并发运行时使用 ThreadLocal 管理驱动程序的需求.

5 - 使用选择列表元素

与其他元素相比，选择列表具有特殊的行为.

Select对象现在将为您提供一系列命令, 用于允许您与 <select> 元素进行交互.

如果您使用的是 Java 或 .NET， 请确保您在代码中已正确加载所需的包. 您可以通过GitHub查看下面示例的完整代码.

请注意，此类仅适用于 HTML 元素 select 和 option. 这个类将不适用于那些通过 div 或 li 并使用JavaScript遮罩层设计的下拉列表.

类型

选择方法的行为可能会有所不同， 具体取决于正在使用的 <select> 元素的类型.

单选

这是标准的下拉对象，其只能选定一个选项.

<select name="selectomatic">
    <option selected="selected" id="non_multi_option" value="one">One</option>
    <option value="two">Two</option>
    <option value="four">Four</option>
    <option value="still learning how to count, apparently">Still learning how to count, apparently</option>
</select>

复选

此选择列表允许同时选定和取消选择多个选项. 这仅适用于具有 multiple 属性的 <select>元素.

<select name="multi" id="multi" multiple="multiple">
    <option selected="selected" value="eggs">Eggs</option>
    <option value="ham">Ham</option>
    <option selected="selected" value="sausages">Sausages</option>
    <option value="onion gravy">Onion gravy</option>
</select>

构建类

首先定位一个 <select> 元素, 然后借助其初始化一个Select 对象. 请注意, 从 Selenium 4.5 开始, 您无法针对禁用的 <select> 元素构建 Select 对象.

        WebElement selectElement = driver.findElement(By.name("selectomatic"));
        Select select = new Select(selectElement);
    select_element = driver.find_element(By.NAME, 'selectomatic')
    select = Select(select_element)
            var selectElement = driver.FindElement(By.Name("selectomatic"));
            var select = new SelectElement(selectElement);
    select_element = driver.find_element(name: 'selectomatic')
    select = Selenium::WebDriver::Support::Select.new(select_element)

  it('Select an option', async function () {

    val selectElement = driver.findElement(By.name("selectomatic"))
    val select = Select(selectElement)

选项列表

共有两种列表可以被获取:

全部选项

获取 <select> 元素中所有选项列表:

        List<WebElement> optionList = select.getOptions();
    option_list = select.options
            IList<IWebElement> optionList = select.Options;
    option_list = select.options


    val optionList = select.getOptions()

选中的选项

获取 <select> 元素中所选中的选项列表. 对于标准选择列表这将只是一个包含一个元素的列表, 对于复选列表则表示包含的零个或多个元素.

        List<WebElement> selectedOptionList = select.getAllSelectedOptions();
    selected_option_list = select.all_selected_options
            IList<IWebElement> selectedOptionList = select.AllSelectedOptions;
    selected_option_list = select.selected_options
    }

    val selectedOptionList = select.getAllSelectedOptions()

选项

Select类提供了三种选择选项的方法. 请注意, 对于复选类型的选择列, 对于要选择的每个元素可以重复使用这些方法.

文本

根据其可见文本选择选项

        select.selectByVisibleText("Four");
    select.select_by_visible_text('Four')
            select.SelectByText("Four");
    select.select_by(:text, 'Four')
    const countElement = await driver.findElement(By.css("option[value='still learning how to count, apparently']"))

    select.selectByVisibleText("Four")

值

根据其值属性选择选项

        select.selectByValue("two");
    select.select_by_value('two')
            select.SelectByValue("two");
    select.select_by(:value, 'two')
    assert.equal(true, await fourElement.isSelected())

    select.selectByValue("two")

序号

根据其在列表中的位置选择选项

        select.selectByIndex(3);
    select.select_by_index(3)
            select.SelectByIndex(3);
    select.select_by(:index, 3)
    assert.equal(true, await twoElement.isSelected())

    select.selectByIndex(3)

禁用的选项

Selenium v4.5

具有 disabled 属性的选项可能无法被选择.

    <select name="single_disabled">
      <option id="sinlge_disabled_1" value="enabled">Enabled</option>
      <option id="sinlge_disabled_2" value="disabled" disabled="disabled">Disabled</option>
    </select>

        Assertions.assertThrows(UnsupportedOperationException.class, () -> {
            select.selectByValue("disabled");
        });
    with pytest.raises(NotImplementedError):
        select.select_by_value('disabled')
            Assert.ThrowsException<InvalidOperationException>(() => select.SelectByValue("disabled"));
    expect {
      select.select_by(:value, 'disabled')
    }.to raise_exception(Selenium::WebDriver::Error::UnsupportedOperationError)
    const select = await new Select(selectElement)

    await assert.rejects(async () => {
      await select.selectByValue("disabled")

    Assertions.assertThrows(UnsupportedOperationException::class.java) {
      select.selectByValue("disabled")
    }

取消选择选项

只有复选类型的选择列表才能取消选择选项. 您可以对要选择的每个元素重复使用这些方法.

        select.deselectByValue("eggs");
    select.deselect_by_value('eggs')
            select.DeselectByValue("eggs");
    select.deselect_by(:value, 'eggs')
    assert.equal(true, await gravyElement.isSelected())

    select.deselectByValue("eggs")