Insert existing TLabels into a dynamically created array of TLabels - delphi

Question

I'm trying to create a dynamic array of TLabels, then insert already existing TLabels created in the IDE into it so I can then use the array in the code.
My purpose is to use this method for several similar processes.
I would like to make it by using loops.
I saw this thread and it was very helpful to understand about creating arrays of TLabels and populating them with TLabels for the desired purposes, but I couldnt find the particular solution for the case when the labels are already created.
Use variables for object name in Delphi
Basically, what I'm trying to automate is this:
var
LabelArray : array of TLabel;
SetLength(LabelArray, 17);
LabelArray[0] := M2;
LabelArray[1] := M3;
.
.
LabelArray[16] := M18
M2 to M18 are 17 labels that are the TLabels already created and positioned on the Form.

Answer 1

You can use the form's FindComponent method to add the labels to your array.
The code below depends on your having declared LabelArray as a private variable at the form level, so that it exists and is visible when the form is created and the code executes. It also hard-codes in 17 as the number of labels, so if you delete or rename a label you'll have an empty spot in the array - I did not include any error checking to make sure a label is found before putting it into the array and the element could end up nil if a label is missing.
procedure TForm1.FormCreate(Sender: TObject);
var
i: Integer;
begin
SetLength(LabelArray, 17);
{
I use Low() and High() here to avoid having multiple places where
you would have to change the code if you end up adding or removing
labels in the future.
Also note that the index into the array starts at 0, so the code that
calls Format() adjusts that index by 2 to start at M2 instead of M0.
}
for i := Low(LabelArray) to High(LabelArray) do
LabelArray[i] := TLabel(FindComponent(Format('M%d', [i + 2])));
end;

Answer 2

If your labels cannot be found using a common name scheme, but you simply want to get all labels on the same panel / group box etc. into the array, you can use the Controls[] property of the parent control:
SetLength(LabelArray, ParentCtrl.ControlCount);
cnt := 0;
for i := 0 to ParentCtrl.ControlCount - 1 do begin
if ParentCtrl.Controls[i] is TLabel then begin
LabelArray[cnt] := TLabel(ParentCtrl.Controls[i]);
Inc(cnt);
end;
end;
SetLength(LabelArray, cnt);
ParentCtrl is the panel / groupbox or even the form itself that is the common parent of all the labels you are interested in.
If you simply want all labels on a form, even if they are located on other controls, you can use the Components[] property of the form in the same way.