Delphi – Is possible to include files (linking) based on a component property

conditional-compilationdelphipascal

Delphi 2007/2009 odd question here:

It's possible, based on a component property defined in design-time, to include files in linking or leave them ?

Example: If I leave SomeProperty true, when compiling, the unit SomeUnit will be included into my project. Otherwise it will not be included.

My second approach to this problem is to deploy a second component, which when dropped in the form (or not) will include the unit in uses clause. But if it can be done with a property, that'll be better.

I want to avoid conditional compilation via IFDEF because that forces the component to be built every time the projects are built. Or not?

I am trying to achieve an easy way of including some units in project, and then those units will provide support for specific databases. Having these into an option, at the connection component, will be ideally easy: Check support and that's done. Uncheck, and get some less KBs in your compiled APP.

edit: I'll stay with the component way for instance. I knew the IFDEF method and things, but that forces the component to be built everytime the projects are built. Or not?

I was trying to achieve an easy way of including some units in project, and then that units will provide support for specific databases. Having these into an option, at the connection component, will be ideally easy: Check support and that's done. Uncheck, and get some less KBs in your compiled APP.

Best Answer

No.

What are you trying to solve?

You could add a postcompiling step that would optionally include some resource based on a component property - but you'd have to do some coding to implement such a feature.

Related Solutions

Delphi: How to use all units and unit references of one project in another project

The way I would go about implementing this would be to create a program to take an existing DPR file and generate a include file that I would then use in my testing application. You can probably do most of this using a tStringlist. This project would be run PRIOR to building your test cases.

var
  OrigDpr : tStringlist;
begin
  OrigDpr := tSTringlist.create;
  OrigDpr.LoadFromFile( originalprojectname );
  while (OrigDpr.Count > 0) and (not SameText('uses',OrigDpr.Strings[0])) do
    OrigDpr.Delete(0);
  // delete the uses line.
  if (OrigDpr.Count > 0) then
    OrigDpr.Delete(0);
  while (OrigDpr.Count > 0) and 
        (not SameText('{$R *.RES}',OrigDpr.Strings[OrigDpr.Count-1]) do
    OrigDpr.Delete(OrigDpr.Count-1);
  // delete the $R reference
  if (OrigDpr.Count > 0) then
    OrigDpr.Delete(OrigDpr.Count-1);

  OrigDpr.SaveToFile( 'pathtotestproject\TESTPROJECT.INC' );
end;

Then in your test DPR, add the following code in your project uses clause. Since the uses clause include file already includes the semicolon, use the include file at the end of your normal test units.:

USES
  // test units go FIRST
  {$I pathtotestproject\TESTPROJECT.INC}

My assumption is that you are performing late/loose binding, which is why all of this is necessary in the first place (the units are not referenced other than being in the DPR). Otherwise just using any of the units would be sufficient enough to have the initialization code executed.

EDIT

Another option would be to have the first program generate a complete unit, and then use this unit in your test application. This will compile in the initialization/finalization code from all of the referenced units. Your test application then would have to use the global repository you mentioned to gain access to these objects.

An important piece here is to make sure that the test project search path includes the source directories for the other project.

Related Topic