How To Execute JavaScript In Selenium WebDriver

Sometimes it is important to run JavaScript directly from the code to get any property of  Browser-BOM,  HTML-DOM  etc.

• The Browser Object Model (BOM) allows JavaScript to "talk to" the browser. It includes Window, Navigator, Screen, History, Location etc.
  
• With the HTML DOM, JavaScript can access and change all the elements of an HTML document. It includes Document, HTML, CSS, Elements etc.

We can execute JavaScript in 2 simple steps:

1. Cast the WebDriver instance to a  JavascriptExecutor
   JavascriptExecutor js = (JavascriptExecutor) driver;
   
2. Execute JavaScript
   js.executeScript("script for execution")

Example:

	package com.example.tests;
	import org.openqa.selenium.JavascriptExecutor;
	import org.openqa.selenium.WebDriver;
	import org.openqa.selenium.firefox.FirefoxDriver;
	import org.testng.annotations.AfterTest;
	import org.testng.annotations.BeforeTest;
	import org.testng.annotations.Test;
	public class JavaScriptExecutionExample {
	WebDriver driver;
	@BeforeTest
	public void setup(){
	driver = new FirefoxDriver();
	}
	@Test
	public void ExecuteJavaScript(){
	driver.get("http://www.google.com/");
	//// Cast WebDrier instance to a JavascriptExecutor
	JavascriptExecutor js = (JavascriptExecutor) driver;
	//// The readyState property returns the (loading) status of the current document: 'document.readyState'
	System.out.println("Document state : "+js.executeScript("return document.readyState"));
	//// Return the domain name of the server that loaded the document: 'document.domain;'
	System.out.println("Domain : "+js.executeScript("return document.domain"));
	//// The title property returns the title of the current document (the text inside the HTML title element): 'document.title'
	System.out.println("Page Title : "+js.executeScript("return document.title"));
	//// The URL property returns the full URL of the current document: 'document.URL'
	System.out.println("URL : "+js.executeScript("return document.URL"));
	//// Return the cookies associated with the current document: 'document.cookie'
	System.out.println("Cookie : "+js.executeScript("return document.cookie"));
	//// Returns the width of a window screen: 'screen.width'
	System.out.println("Screen Width : "+js.executeScript("return screen.width"));
	//// Return JavaScript Errors associated with the current window: 'window.jsErrors'
	System.out.println("Windows js errors : "+js.executeScript("return window.jsErrors"));
	}
	@AfterTest
	public void tearDown(){
	driver.quit();
	}
	}

view raw JavaScriptExecutionExample.java hosted with ❤ by GitHub