JavaScriptExecutor in Selenium

Selenium is a popular open-source web-based automation tool. Sometimes, Selenium webdriver faces problems in interacting with a few web elements, For example, the user opens a website and there is an unexpected pop-up window that will prevent the webdriver from performing operations and produce inaccurate results. This is where JavascriptExecutor comes into use.

What is JavaScriptExecutor in Selenium?

JavaScriptExecutor is an interface that is used to execute JavaScriprt through selenium webdriver. JavaScript is a programming language that interacts with HTML in a browser, and to use this function in Selenium, JavascriptExecutor is required.

JavascriptExecutor Provides Two Methods:

1. ExecuteScript
2. ExecuteAsyncScript

1. ExecuteScript

This method executes javaScript in the currently selected window or frame. The script runs as an anonymous function and the script can return values. Data types returned are :

• WebElement
• List
• String
• Long
• Boolean

2. ExecuteAsyncScript

This method is used to execute the asynchronous Javascript in the current window or frame. An asynchronous Javascript executed is a single thread while the rest of the page continuous parsing. which enhances the performance.

Get Started with JavaScriptExecutor

1. Import the package

Import org.openqa.selenium.JavascriptExecutor;

2. Create a reference

JavascriptExecutor js = (JavascriptExecutor) driver;

3. Call the JavascriptExecutor method

js.executeScript(script, args);

Examples of JavascriptExecutor in Selenium 

Example 1. JavascriptExecutor in Selenium to refresh the browser window

JavascriptExecutor js = (JavascriptExecutor) driver;

js.executeScript(“location.reload()”);

Example 2. JavascriptExecutor in Selenium to send text

JavascriptExecutor js = (JavascriptExecutor) driver;

js.executeScript(“document.getElementByID(‘element id ’).value = ‘xyz’;”);

Example 3. Generate Alert Pop Window

JavascriptExecutor js = (JavascriptExecutor)driver;

Js.executeScript(“alert(‘hello world’);”);

Example 4. Get InnerText of a Webpage

JavascriptExecutor js = (JavascriptExecutor)driver;

string sText =  js.executeScript(“return document.documentElement.innerText;”).toString();

Example 5. Get Title of a WebPage

JavascriptExecutor js = (JavascriptExecutor)driver;

string sText =  js.executeScript(“return document.title;”).toString();

Example 6. Scroll Page

JavascriptExecutor js = (JavascriptExecutor)driver;

 //Vertical scroll – down by 150  pixels

 js.executeScript(“window.scrollBy(0,150)”);

Click an Element using JavaScripExecutor

In the example, we use selenium webdriver and the javascriptexecutor to open geeksforgeeks website and click an element.

Explanation of the code: The above script is for opening Edge Browser and navigating to geeksforgeeks website and clicking an element using JavaScriptExecutor. So let’s see how it works:

1. Set a system property “webdriver.edge.driver” to the path of youredgedriver.exe file and instantiate a Edge driver class: System.setProperty(“webdriver.edge.driver”,”edgedriver location”);
2. Maximize the window: driver.manage().window().maximize();  
3. To open the URL: driver.get(“URL link”)
4. Get the element for Java using finddby xpath method “driver.findElement(By.xpath(“xpath address”));”
5. Create reference for JavaScriptExecutor “JavascriptExecutor js = (JavascriptExecutor) driver;”
6. Call the JavascriptExecutor method and pass the webelement for clicking “js.executeScript(“arguments[0].click();”,webelement);”

Output: