查询网络元素
One of the most fundamental aspects of using Selenium is obtaining element references to work with. Selenium offers a number of built-in locator strategies to uniquely identify an element. There are many ways to use the locators in very advanced scenarios. For the purposes of this documentation, let’s consider this HTML snippet:
<ol id="vegetables">
<li class="potatoes">…
<li class="onions">…
<li class="tomatoes"><span>Tomato is a Vegetable</span>…
</ol>
<ul id="fruits">
<li class="bananas">…
<li class="apples">…
<li class="tomatoes"><span>Tomato is a Fruit</span>…
</ul>
First matching element
Many locators will match multiple elements on the page. The singular find element method will return a reference to the first element found within a given context.
Evaluating entire DOM
When the find element method is called on the driver instance, it returns a reference to the first element in the DOM that matches with the provided locator. This value can be stored and used for future element actions. In our example HTML above, there are two elements that have a class name of “tomatoes” so this method will return the element in the “vegetables” list.
WebElement vegetable = driver.findElement(By.className("tomatoes"));
vegetable = driver.find_element(By.CLASS_NAME, "tomatoes")
var vegetable = driver.FindElement(By.ClassName("tomatoes"));
vegetable = driver.find_element(class: 'tomatoes')
const vegetable = await driver.findElement(By.className('tomatoes'));
val vegetable: WebElement = driver.findElement(By.className("tomatoes"))
Evaluating a subset of the DOM
Rather than finding a unique locator in the entire DOM, it is often useful to narrow the search to the scope of another located element. In the above example there are two elements with a class name of “tomatoes” and it is a little more challenging to get the reference for the second one.
One solution is to locate an element with a unique attribute that is an ancestor of the desired element and not an ancestor of the undesired element, then call find element on that object:
WebElement fruits = driver.findElement(By.id("fruits"));
WebElement fruit = fruits.findElement(By.className("tomatoes"));
fruits = driver.find_element(By.ID, "fruits")
fruit = fruits.find_element(By.CLASS_NAME,"tomatoes")
IWebElement fruits = driver.FindElement(By.Id("fruits"));
IWebElement fruit = fruits.FindElement(By.ClassName("tomatoes"));
fruits = driver.find_element(id: 'fruits')
fruit = fruits.find_element(class: 'tomatoes')
const fruits = await driver.findElement(By.id('fruits'));
const fruit = fruits.findElement(By.className('tomatoes'));
val fruits = driver.findElement(By.id("fruits"))
val fruit = fruits.findElement(By.className("tomatoes"))
Java and C#
WebDriver
, WebElement
and ShadowRoot
classes all implement a SearchContext
interface, which is
considered a role-based interface. Role-based interfaces allow you to determine whether a particular
driver implementation supports a given feature. These interfaces are clearly defined and try
to adhere to having only a single role of responsibility.
Optimized locator
A nested lookup might not be the most effective location strategy since it requires two separate commands to be issued to the browser.
To improve the performance slightly, we can use either CSS or XPath to find this element in a single command. See the Locator strategy suggestions in our Encouraged test practices section.
For this example, we’ll use a CSS Selector:
WebElement fruit = driver.findElement(By.cssSelector("#fruits .tomatoes"));
fruit = driver.find_element(By.CSS_SELECTOR,"#fruits .tomatoes")
var fruit = driver.FindElement(By.CssSelector("#fruits .tomatoes"));
fruit = driver.find_element(css: '#fruits .tomatoes')
const fruit = await driver.findElement(By.css('#fruits .tomatoes'));
val fruit = driver.findElement(By.cssSelector("#fruits .tomatoes"))
All matching elements
There are several use cases for needing to get references to all elements that match a locator, rather than just the first one. The plural find elements methods return a collection of element references. If there are no matches, an empty list is returned. In this case, references to all fruits and vegetable list items will be returned in a collection.
List<WebElement> plants = driver.findElements(By.tagName("li"));
plants = driver.find_elements(By.TAG_NAME, "li")
IReadOnlyList<IWebElement> plants = driver.FindElements(By.TagName("li"));
plants = driver.find_elements(tag_name: 'li')
const plants = await driver.findElements(By.tagName('li'));
val plants: List<WebElement> = driver.findElements(By.tagName("li"))
Get element
Often you get a collection of elements but want to work with a specific element, which means you need to iterate over the collection and identify the one you want.
List<WebElement> elements = driver.findElements(By.tagName("li"));
for (WebElement element : elements) {
System.out.println("Paragraph text:" + element.getText());
}
from selenium import webdriver
from selenium.webdriver.common.by import By
driver = webdriver.Firefox()
# Navigate to Url
driver.get("https://www.example.com")
# Get all the elements available with tag name 'p'
elements = driver.find_elements(By.TAG_NAME, 'p')
for e in elements:
print(e.text)
using OpenQA.Selenium;
using OpenQA.Selenium.Firefox;
using System.Collections.Generic;
namespace FindElementsExample {
class FindElementsExample {
public static void Main(string[] args) {
IWebDriver driver = new FirefoxDriver();
try {
// Navigate to Url
driver.Navigate().GoToUrl("https://example.com");
// Get all the elements available with tag name 'p'
IList < IWebElement > elements = driver.FindElements(By.TagName("p"));
foreach(IWebElement e in elements) {
System.Console.WriteLine(e.Text);
}
} finally {
driver.Quit();
}
}
}
}
require 'selenium-webdriver'
driver = Selenium::WebDriver.for :firefox
begin
# Navigate to URL
driver.get 'https://www.example.com'
# Get all the elements available with tag name 'p'
elements = driver.find_elements(:tag_name,'p')
elements.each { |e|
puts e.text
}
ensure
driver.quit
end
const {Builder, By} = require('selenium-webdriver');
(async function example() {
let driver = await new Builder().forBrowser('firefox').build();
try {
// Navigate to Url
await driver.get('https://www.example.com');
// Get all the elements available with tag 'p'
let elements = await driver.findElements(By.css('p'));
for(let e of elements) {
console.log(await e.getText());
}
}
finally {
await driver.quit();
}
})();
import org.openqa.selenium.By
import org.openqa.selenium.firefox.FirefoxDriver
fun main() {
val driver = FirefoxDriver()
try {
driver.get("https://example.com")
// Get all the elements available with tag name 'p'
val elements = driver.findElements(By.tagName("p"))
for (element in elements) {
println("Paragraph text:" + element.text)
}
} finally {
driver.quit()
}
}
Find Elements From Element
It is used to find the list of matching child WebElements within the context of parent element. To achieve this, the parent WebElement is chained with ‘findElements’ to access child elements
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import java.util.List;
public class findElementsFromElement {
public static void main(String[] args) {
WebDriver driver = new ChromeDriver();
try {
driver.get("https://example.com");
// Get element with tag name 'div'
WebElement element = driver.findElement(By.tagName("div"));
// Get all the elements available with tag name 'p'
List<WebElement> elements = element.findElements(By.tagName("p"));
for (WebElement e : elements) {
System.out.println(e.getText());
}
} finally {
driver.quit();
}
}
}
from selenium import webdriver
from selenium.webdriver.common.by import By
driver = webdriver.Chrome()
driver.get("https://www.example.com")
# Get element with tag name 'div'
element = driver.find_element(By.TAG_NAME, 'div')
# Get all the elements available with tag name 'p'
elements = element.find_elements(By.TAG_NAME, 'p')
for e in elements:
print(e.text)
using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;
using System.Collections.Generic;
namespace FindElementsFromElement {
class FindElementsFromElement {
public static void Main(string[] args) {
IWebDriver driver = new ChromeDriver();
try {
driver.Navigate().GoToUrl("https://example.com");
// Get element with tag name 'div'
IWebElement element = driver.FindElement(By.TagName("div"));
// Get all the elements available with tag name 'p'
IList < IWebElement > elements = element.FindElements(By.TagName("p"));
foreach(IWebElement e in elements) {
System.Console.WriteLine(e.Text);
}
} finally {
driver.Quit();
}
}
}
}
require 'selenium-webdriver'
driver = Selenium::WebDriver.for :chrome
begin
# Navigate to URL
driver.get 'https://www.example.com'
# Get element with tag name 'div'
element = driver.find_element(:tag_name,'div')
# Get all the elements available with tag name 'p'
elements = element.find_elements(:tag_name,'p')
elements.each { |e|
puts e.text
}
ensure
driver.quit
end
const {Builder, By} = require('selenium-webdriver');
(async function example() {
let driver = new Builder()
.forBrowser('chrome')
.build();
await driver.get('https://www.example.com');
// Get element with tag name 'div'
let element = driver.findElement(By.css("div"));
// Get all the elements available with tag name 'p'
let elements = await element.findElements(By.css("p"));
for(let e of elements) {
console.log(await e.getText());
}
})();
import org.openqa.selenium.By
import org.openqa.selenium.chrome.ChromeDriver
fun main() {
val driver = ChromeDriver()
try {
driver.get("https://example.com")
// Get element with tag name 'div'
val element = driver.findElement(By.tagName("div"))
// Get all the elements available with tag name 'p'
val elements = element.findElements(By.tagName("p"))
for (e in elements) {
println(e.text)
}
} finally {
driver.quit()
}
}
Get Active Element
It is used to track (or) find DOM element which has the focus in the current browsing context.
import org.openqa.selenium.*;
import org.openqa.selenium.chrome.ChromeDriver;
public class activeElementTest {
public static void main(String[] args) {
WebDriver driver = new ChromeDriver();
try {
driver.get("http://www.google.com");
driver.findElement(By.cssSelector("[name='q']")).sendKeys("webElement");
// Get attribute of current active element
String attr = driver.switchTo().activeElement().getAttribute("title");
System.out.println(attr);
} finally {
driver.quit();
}
}
}
from selenium import webdriver
from selenium.webdriver.common.by import By
driver = webdriver.Chrome()
driver.get("https://www.google.com")
driver.find_element(By.CSS_SELECTOR, '[name="q"]').send_keys("webElement")
# Get attribute of current active element
attr = driver.switch_to.active_element.get_attribute("title")
print(attr)
using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;
namespace ActiveElement {
class ActiveElement {
public static void Main(string[] args) {
IWebDriver driver = new ChromeDriver();
try {
// Navigate to Url
driver.Navigate().GoToUrl("https://www.google.com");
driver.FindElement(By.CssSelector("[name='q']")).SendKeys("webElement");
// Get attribute of current active element
string attr = driver.SwitchTo().ActiveElement().GetAttribute("title");
System.Console.WriteLine(attr);
} finally {
driver.Quit();
}
}
}
}
require 'selenium-webdriver'
driver = Selenium::WebDriver.for :chrome
begin
driver.get 'https://www.google.com'
driver.find_element(css: '[name="q"]').send_keys('webElement')
# Get attribute of current active element
attr = driver.switch_to.active_element.attribute('title')
puts attr
ensure
driver.quit
end
const {Builder, By} = require('selenium-webdriver');
(async function example() {
let driver = await new Builder().forBrowser('chrome').build();
await driver.get('https://www.google.com');
await driver.findElement(By.css('[name="q"]')).sendKeys("webElement");
// Get attribute of current active element
let attr = await driver.switchTo().activeElement().getAttribute("title");
console.log(`${attr}`)
})();
import org.openqa.selenium.By
import org.openqa.selenium.chrome.ChromeDriver
fun main() {
val driver = ChromeDriver()
try {
driver.get("https://www.google.com")
driver.findElement(By.cssSelector("[name='q']")).sendKeys("webElement")
// Get attribute of current active element
val attr = driver.switchTo().activeElement().getAttribute("title")
print(attr)
} finally {
driver.quit()
}
}