Classes in VBScript

Classes in VBScript

Here is an example that shows how we can create a class in QTP. Once we define the class, we can create its objects and then access its method and properties.

'declare the class book.

Class Book

dim bn,bp
'class has 2 variable members bn and bp.

public Property Get bookname()
    ' Get bookname property gets the book name of the object of Book
  bookname = bn
End Property

public Property Let  bookname(x)
  bn = x
   ' Let  bookname property assigns value to the book name of the object of Book
End Property


public Property Get price()
price = bp
End Property

public Property Let  price(x)
bp = x
End Property


function  discountedPrice()
print bp-20
'We can have functions and procedures inside class to process memeber variables
End function


Private Sub Class_Initialize   ' Setup Initialize event.

MsgBox("Object of Book Class created")

End Sub

Private Sub Class_Terminate   ' Setup Terminate event.

MsgBox("Object of Book Class destroyed")

End Sub


End Class

Set b1 = new  Book
'createing the object b2 of the class Book.

b1.bookname = "QTP Tutorials"
b1.price = 220
'assigning value to the object b1

print b1.bookname()
'getting the value of the property bookname.

'accessing the function in class
b1.discountedPrice()

Set b1 = nothing

QTP does support object oriented programming to some extent. We can create constructors and destructors in vbscript classes using class_initialize and class_terminate methods. class_initialize method acts like constructor function which gets called automatically when we create an object of the class. This is how we can create and use the classes in QTP.