Question

What’s wrong with my code? I’m getting this error:

[dcc32 Error] Unit6.pas(83): E2012 Type of expression must be BOOLEAN

function checkver(): boolean;
begin
  //some code here
end;

function refresh(): boolean;
begin
  //some code here
end;

procedure TForm6.FormCreate(Sender: TObject);
begin
  if checkver() then
    if refresh() then  //Error is HERE!!
      //some code here
end;

(full code)

Answer 1

TControl (which your form class descends from) has a Refresh method of its own, and it doesn’t return a Boolean. The scope of that method is closer than the scope of the unit-level method by the same name because you’re writing code in a method of that class, so the compiler binds with the Refresh method, not the refresh function.

Call <unitname>.refresh to get the unit-level function instead of the method.