reteiving values from a function from inside the page declaration

I have an app in which I have a label control to which the text property is set depending on the value of a function contained in the page. That function takes an argument

as a simple example:

public function Test(arg1 as integer) as string
return arg1.tostring
end function

how do I declare this in the page delaratio?

text='<%# test(4)%>' is not working...

so how should i do this?
...