Object Repository and Descriptive Programming in QTP

Pre Requisites: Basic of OOPS
Object Repository (OR) and Descriptive Programming (DP) are the two ways by which QTP recognize the objects present in your application under test (AUT).
First let see about OR, this is one of the greatest features that QTP has. You can easily capture all the objects from AUT and store it into QTP’s OR. During the play back QTP use this OR to identify the object on which the action is to be performed. Here QTP take care of all the object and it properties, you have a very good UI to edit an existing OR.
Let us look at an example Google Search button present in the Google’s home page.
We recognize the search button as below.

The same is stored into QTP OR as shown below.

So QTP use the properties of the object to identify each objects uniquely present in AUT.
The Description properties namely type, name and html tag are the mandatory properties used to identify the objects. If more than one object has all the three properties same then it uses other properties (assistive properties) of the object to identify the correct object.
What if there are more than one identical objects in same web page or window?
QTP can use the following types of ordinal identifiers to identify such objects:

• Index. Indicates the order in which the object appears in the application code relative to other objects with an otherwise identical description.
• Location. Indicates the order in which the object appears within the parent window, frame, or dialog box relative to other objects with an otherwise identical description.
• CreationTime. (Browser object only.) Indicates the order in which the browser was opened relative to other open browsers with an otherwise identical description.

The ordinal identifier assigns the object a numerical value(index starts with zero) that indicates its order relative to other objects with an otherwise identical description (objects that have the same values for all properties specified in the mandatory and assistive property lists). This ordered value enables QuickTest to create a unique description when the mandatory and assistive properties are not sufficient to do so.
Below screen shot shows the Ordinal identifier value for the browser object.

Now to click Google Search button, you start from the browser hierarchy.
Browser (“Google”).Page (“Google”).WebButton (“Google Search”).Click
Now we are able to perform actions on the objects present in OR,then why DP ?
DP is a way in which you describe the object by writing your own code or script,instead of storing the objects in OR.
QTP records the properties of the objects at the time of recording and stores in OR, during playback it compares the properties of those in OR with run time objects and perform action on them. But what if the object is a dynamically generated during run time?.Let me give a situation where OR will not help you to identify an object. If you want to close all opened browser automatically before you start executing your scripts, it is not possible to store all the opened browser objects into OR. So this can be solved by using OR and regular expression.
Here in DP you have option to define the properties of objects in the script itself. There are two ways by which you can define your objects.
In first method, you can describe an object directly in a statement by specifying property:=value pairs describing the object.
The same Google search button present in OR can be described by code as
Browser(“google”).page(“google”).webbutton(“name:=Google Search”,”type:= Submit”).click
In above statement Browser,Page are identified from OR webbutton is identified from DP,so the webbutton need not to be captured and stored into OR.So here we described an object with property and value pair, first property is name which has value as Google Search and another property is type which has value of Submit.
Second way to define a DP object is by using the Description object,You start by defining an object for example
Set mygooglesearch = Description.Create()
Then you declare the property name and value pair for that object
mygooglesearch(“name”).value =”Google Search”
mygooglesearch(“type”).value =”Submit”
Now the above object can be used in the script instead of the object present in OR as
Browser(“Google”).Page(“Google”).webbutton(mygooglesearch).click
Now to release the object and to free the memory,set that object to Nothing
Set mygooglesearch = Nothing
NOTE: When using programmatic descriptions from a specific point within a test object hierarchy, you must continue to use programmatic descriptions from that point onward within the same statement. For example
Browser(mygoogle).page(“google”).webbutton(“Google Search”).click is invalid because once you start using DP you can’t come back to OR for that statement.
Browser(mygoogle).page(mygoogle).webbutton(mygooglsearch).click is a valid statement
What are the other advantages of DP?

1. Getting Object collections.
2. If same object appears in different page/window then instead of capturing the object in every  page/window use one DP object.

Look at this example on how to use DP to close all browser.
Summary:
This post explains  how QTP identifies objects and how to handle dynamic object using DP. OR the way in which QTP automatically stores the object, on the other hand DP is the way how we store the objects. DP is same as declaring a variable and assigning a value to it,here instead of value we assign object properties to the declared object.