on method1(input) -- parametrized handler display dialog input end method1 method1("Hey There. I am Nayan Seth.") -- passing parameters value
Explanation: Parametrized Handlers are functions in which a variable is passed.
In the above example I have created a handler named method1 and I have also passed variable input to the handler.
In the method1 block, I have displayed a dialog with the text of variable input.
Now when I call method1, I have to pass the information of parameters inside the round brackets. When we run the script a dialog will pop up with text “Hey There. I am Nayan Seth.”
on area(radius) -- parametrized handler set circleArea to pi * (radius ^ 2) display dialog "Area of Circle is " & circleArea end area set condition to false repeat until condition is true set temp to display dialog "Enter radius of Circle" default answer "" set r to text returned of temp try set r to r as integer on error display dialog "Enter a valid number" end try if class of r is integer then set condition to true area(r) end if end repeat
Explanation: Huge program! Don’t worry... It’s super simple.
This program calculates area of circle by taking radius as input from user.
I have defined a handler named area(radius). It computes area of circle and displays it in a dialog.
But since the handler is parametrized, it needs value for the radius. [Refer to 13.3.3] To get the value of the radius, I asked for user input. But we know that user can type a string too.
So I used repeat command so that if error occurs, user can re-enter the value of radius.
The value of radius that I get from user is stored in variable r. This value is passed to handler named area(r).
Figure 14.3.2 Area of Circle