How to list all data modules opened in an Application?

[vfclists]

When I am opening a form and need to check whether an instance of the form exists I use this code:

Code: [Select]

function FindFormT(formClass: string):TForm;
var
  i, j:integer;
  upFormClass: string;
begin
  result := nil;
  upformClass := 'T' + UpperCase(formClass);
  for i := 0 to Screen.FormCount-1 do
  begin
    if UpperCase(Screen.Forms[i].ClassName) = upFormClass then
    begin
      result := Screen.Forms[i];
    end;
 end;

end; 
What equivalent code should be used for data modules? Does the Application object have a data module count?

[taazz]

When I am opening a form and need to check whether an instance of the form exists I use this code:

Code: [Select]

function FindFormT(formClass: string):TForm;
var
  i, j:integer;
  upFormClass: string;
begin
  result := nil;
  upformClass := 'T' + UpperCase(formClass);
  for i := 0 to Screen.FormCount-1 do
  begin
    if UpperCase(Screen.Forms[i].ClassName) = upFormClass then
    begin
      result := Screen.Forms[i];
    end;
 end;

end; 
What equivalent code should be used for data modules? Does the Application object have a data module count?

No but the screen object does take a look at Screen.DataModuleCount; and  Screen.DataModules[] properties.
Just a question do you have forms in dlls?

[vfclists]

No, I don't have forms in dlls. Is there some reason why you are asking?

No but the screen object does take a look at Screen.DataModuleCount; and  Screen.DataModules[] properties.
Just a question do you have forms in dlls?

[taazz]

because I would code the above routine as

Code: [Select]

function FindForm(const aClass:TClass):TForm;
var
  vCnt: Integer;
begin
  for vCnt := 0 to Screen.FormCount -1 do
    if Screen.Forms[vCnt].ClassType = aClass then begin
      Result := Screen.Forms[vCnt];
      Break;
    end;
end;

Calling it like

FindForm(TForm3);

that will not work if the form is in a dll though.

[vfclists]

You learn something new everyday
Do you use form dlls in Lazarus on Windows, and Linux as well? I am thinking of it as something that will minimize my compile-edit-debug cycles?

because I would code the above routine as

Code: [Select]

function FindForm(const aClass:TClass):TForm;
var
  vCnt: Integer;
begin
  for vCnt := 0 to Screen.FormCount -1 do
    if Screen.Forms[vCnt].ClassType = aClass then begin
      Result := Screen.Forms[vCnt];
      Break;
    end;
end;

Calling it like

FindForm(TForm3);

that will not work if the form is in a dll though.

[taazz]

No I don't, using the forms from dlls will increase your debug cycles, you see any small change on the internals of your program might trigger a SIGSEGV exception on the dll if they are not compiled as well with the changes in. This makes it harder to debug not easier.