In the previous tutorial, we introduced you with another
automation testing tool named as Firebug. We also created our own automation
script manually using Firebug and its capabilities. We also learned to affix
desired modifications into our script.
Moving ahead, in this tutorial we would have a look at the
various types of locators in Selenium and their accessibility technique to
build test scripts. Thus this tutorial is comprised of the detailed
introduction to various types of locators.
This is our 5th tutorial in Selenium Tutorial series.
What is Locator?
Locator can be termed as an address that identifies a web
element uniquely within the webpage. Locators are the HTML properties of a web
element which tells the Selenium about the web element it need to perform
action on.
Using Selenium Xpath and Other Locators
There is a diverse range of web elements. The most common
amongst them are:
Text box
Button
Drop Down
Hyperlink
Check Box
Radio Button
Types of Locators
Identifying these elements has always been a very tricky
subject and thus it requires an accurate and effective approach. Thereby, we
can assert that more effective the locator, more stable will be the automation
script. Essentially every Selenium command requires locators to find the web
elements. Thus, to identify these web elements accurately and precisely we have
different types of locators.
Types of Locators in Selenium 1
Now let’s understand further by exercising each of them
independently.
Before we start with the locators, let me take a moment to
introduce the application under test. We would be using
“https://accounts.google.com/” for locating different types of web elements
using different locator types.
Using ID as a Locator
The best and the most popular method to identify web element
is to use ID. The ID of an each element is alleged to be unique.
Types of Locators in Selenium 2
In this sample, we would access “Email” text box present in
the login form at gmail.com.
Finding an ID of a web element using Firebug
Step 1: Launch the web browser (Firefox) and navigate to
“https://accounts.google.com/”.
Step 2: Open firebug (either by pressing F12 or via tools).
Step 3: Click on the inspect icon to identify the web
element.
Selenium Locators 1
Step 4: Hover on the web element (Email textbox in our case)
on which we desire to perform some action. In the firebug section, one can see
the corresponding html tags being highlighted.
Selenium Locators 2
Step 5: Be cognizant about the ID attribute and take a note
of it. Now we need to verify if the ID indentified is able to find the element
uniquely and flawlessly.
Syntax: id = id of the element
In our case, the id is “Email”.
Alternative approach:
Instead of following step 2 to 4, we can directly locate /
inspect the web element by right clicking on the web element (Email Textbox)
whose locator value we need to inspect and clicking on the option “Inspect
Element with Firebug”. Thus, this click event triggers the expansion of firebug
section and the corresponding html tag would be highlighted.
Selenium Locators 3
Verify the locator value
Assuming that the browser is open and is re-directed to
“https://accounts.google.com/”.
Step 1: Launch Selenium IDE.
Step 2: Click on the first row in the editor section.
Step 3: Type “id=Email” i.e. the locator value in the target
box.
Step 4: Click on the Find Button. If the provided locator
value is legitimate then the Email textbox will be highlighted with yellow
color with a florescent green border around the field. If the locator value
provided is incorrect, an error message would be printed in the log pane at the
bottom of Selenium IDE.
Case 1 – Locator Value = Correct
Selenium Locators 4
Case 2 – Locator Value = Incorrect
Selenium Locators 5
Step 5: In order to verify further, user can also execute
“type” command against the given target by providing some value in the “Value”
field. If the execution of the command enters the specified value in the Email
text box that means the identified locator type is correct and accessible.
Using ClassName as a Locator
There is only a subtle difference between using ID as a
locator and using classname as a locator.
In this sample, we would access “Need Help?” hyperlink
present at the bottom of the login form at gmail.com.
Finding a classname of a web element using Firebug
Step 1: Locate / inspect the web element (“Need help?” link
in our case) by right clicking on the web element whose locator value we need
to inspect and clicking on the option “Inspect Element with Firebug”.
Step 2: Be cognizant about the classname attribute and take
a note of it. Now we need to verify if the classname indentified is able to
find the element uniquely and accurately.
Selenium Locators 6
Syntax: class = classname of the element
In our case, the classname is “need-help-reverse”
Verify the locator value
Step 1: Type “class= need-help-reverse” in the target box in
the Selenium IDE.
Step 2: Click on the Find Button. Notice that the hyperlink
will be highlighted with yellow color with a florescent green border around the
field.
(Click to view enlarged image)
Selenium Locators 7
Using name as a Locator
Locating a web element using name is very much analogous to previous
two locator types. The only difference lies in the syntax.
In this sample, we would access “Password” text box present
in the login form at gmail.com.
Syntax: name = name of the element
In our case, the name is “Passwd”.
Verify the locator value
Step 1: Type “name= Passwd” in the target box and click on
the Find Button. Notice that the “Password” textbox would be highlighted.
------------
Using Link Text as a Locator
All the hyperlinks on a web page can be indentified using
Link Text. The links on a web page can be determined with the help of anchor
tag (<a>). The anchor tag is used to create the hyperlinks on a web page
and the text between opening and closing of anchor tags constitutes the link
text (<a>Some Text</a>).
In this sample, we would access “Create an account” link
present at the bottom of the login form at gmail.com.
Finding a link text of a web element using Firebug
Step 1: Locate / inspect the web element (“Create an
account” link in our case) by right clicking on the web element whose locator
value we need to inspect and clicking on the option “Inspect Element with
Firebug”.
Step 2: Be cognizant about the text present within the
<a> </a> tags and take a note of it. Hence this text will be used
to identify the link on a web page uniquely.
(Click to view enlarged image)
Selenium Locators 8
Syntax: link = link text of the element
In our case, the link text is “Create an account”.
Verify the locator value
Step 1: Type “link=Create an account” i.e. the locator value
in the target box in Selenium IDE.
Step 2: Click on the Find Button. Notice that the link would
be highlighted with yellow color with a florescent green border around the
field.
Selenium Locators 9
Using Xpath as a Locator
Xpath is used to locate a web element based on its XML path.
XML stands for Extensible Markup Language and is used to store, organize and
transport arbitrary data. It stores data in a key-value pair which is very much
similar to HTML tags. Both being mark up languages and since they fall under
the same umbrella, xpath can be used to locate HTML elements.
The fundamental behind locating elements using Xpath is the
traversing between various elements across the entire page and thus enabling a
user to find an element with the reference of another element.
Xpath can be created in two ways:
Relative Xpath
Relative Xpath begins from the current location and is
prefixed with a “//”.
For example: //span[@class=’Email’]
Absolute Xpath
Absolute Xpath begins with a root path and is prefixed with
a “/”.
For example: /html/body/div/div[@id=’Email’]
Key Points:
The success rate of finding an element using Xpath is too
high. Along with the previous statement, Xpath can find relatively all the
elements within a web page. Thus, Xpaths can be used to locate elements having
no id, class or name.
Creating a valid Xpath is a tricky and complex process.
There are plug-ins available to generate Xpath but most of the times, the
generated Xpaths fails to identify the web element correctly.
While creating xpath, user should be aware of the various
nomenclatures and protocols.
Selenium Xpath Examples
Xpath Checker
Creating Xpath becomes a little simpler by using Xpath
Checker. Xpath Checker is a firefox add-on to automatically generate Xpath for
a web element. The add-on can be downloaded and installed like any other
plug-in. The plug-in can be downloaded from
“https://addons.mozilla.org/en-US/firefox/addon/xpath-checker/”.
As soon as the plug-in is installed, it can be seen in the
context menu by right clicking any element whose xpath we want to generate.
Selenium Locators 10
Click on the “View Xpath” to see the Xpath expression of the
element. An editor window would appear with the generated Xpath expression. Now
user has the liberty to edit and modify the generated Xpath expression. The
corresponding results would be updated cumulatively.
Selenium Locators 11
Note that the Xpath Checker is available for other browsers
as well.
But re-iterating the fact, that most of the times, the
generated Xpaths fails to identify the web element rightly. Thus, it is
recommended to create our own Xpath following the pre defined rules and
protocols.
In this sample, we would access “Google” image present at
the top of the login form at gmail.com.
Creating a Xpath of a web element
Step 1: Type “//img[@class=’logo’]” i.e. the locator value
in the target box within the Selenium IDE.
Syntax: Xpath of the element
Step 2: Click on the Find Button. Notice that the image
would be highlighted with yellow color with a florescent green border around
the field.
Selenium Locators 12
Conclusion
Here are the cruxes of this article.
Locators are the HTML properties of a web element which
tells the Selenium about the web element on which it needs to perform actions.
There is a wide range of web elements that a user may have
to interact with on a regular basis. Some of them are: Text box, Button, Drop
Down, Hyperlink, Check Box, and Radio Button.
With the varied range of web elements comes a vast province
of strategies/approaches to locate these web elements.
Some of the extensively used locator types are: ID,
ClassName, Link Text, Xpath, CSS Selectors and Name.
Note: Owing to the fact that creating CSS Selector and Xpath
requires a lot of efforts and practice, thus the process is only exercised by
more sophisticated and trained users.
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