Please can you give me a example to write UDF for win32 using c++
or delphi language.

Example:
C++
======
double GetArea(double Height; double Width) {
Return Height * Width;
}

Delphi
=====
function GetArea(Height, Width: Double): Double;
begin
Result := Height * Double;
end;

Notes:
How to get param value (Height, Width)?