Using a simple calculator we separate the business logic from the front end GUI.
To pass data to the middleware scripts we use the attribute setData, which would collect the
labels from the widgets named 'value1' and 'value2' WHEN the action event is called. It must be noted that
the 'named' widgets are resolved when needed (when the action event is called)
The uri request will be in the form of URL GET request add.php?value1=5&value2=7
To add two values in php, you just use the '+' operator.
To subtract, '-', to divide, '/', to multiply '*'.
PHP has access to far more mathematical functions from various libraries.
For a more complete reference on php, please refer to www.php.net