Passing and Receiving values (parameters) in Custom workflow

Just thought of posting this code snippet on input/output parameters in CWF. In most of the places it explains well on how to declare the parameters, but not using of get, set methods in the code.

Here how we declare them;

[RequiredArgument]
[Input("Salary")]
public InArgument<Double> SalaryVal { get; set; }

[OutputAttribute("Tax")]
public OutArgument<Double> TaxVal { get; set; }

...and this is how you associate to the code within the Execute method;

protected override void Execute(CodeActivityContext executionContext)
{
//...........
//...........

Double _salaryVal = SalaryVal.Get(executionContext);

// Calculation goes here
// and return to _taxVal

TaxVal.Set(executionContext, _taxVal);

}