TFindDialog: what changed

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Title: TFindDialog

New		Line
1	+	TFindDialog ![](/wiki-images/9/9e/Tfinddialog.png) is a component that aids in searching information. It can be found on the [[Dialogs tab]] of the [[Component Palette]].
2	+
3	+	It is important to know that the dialog itself does not perform a search; it just provides a user interface for all the search parameters. To activate a FindDialog, call its `Execute()` [[Function\|function]]. Create an `OnFind` [[Method\|method]] in which the search itself is performed.
4	+
5	+	<figure>
6	+	<img src="component-TFindDialog.png" title="component-TFindDialog.png" />
7	+	<figcaption>component-TFindDialog.png</figcaption>
8	+	</figure>
9	+
10	+	## Usage
11	+
12	+	The following examples illustrate usage of TFindDialog for search a specific phrase within the text stored in a memo ([[TMemo]]).
13	+
14	+	``` pas
15	+	procedure TForm1.Button1Click(Sender: TObject);
16	+	begin
17	+	FindDialog1.Execute();
18	+	end;
19	+
20	+	procedure TForm1.FindDialog1Find(Sender: TObject);
21	+	var
22	+	k: integer;
23	+	begin
24	+	with Sender as TFindDialog do begin
25	+	k := Pos(FindText, Memo1.Lines.Text);
26	+	if k > 0 then begin
27	+	Memo1.SelStart := k - 1;
28	+	Memo1.SelLength := Length(FindText);
29	+	Memo1.SetFocus; // Memo1 must be activated, otherwise the selection effect will not be displayed
30	+	end else
31	+	Beep();
32	+	end;
33	+	end;
34	+	```
35	+
36	+	If you want to repeat the operation several times with the same search text you must remember the last found position and continue searching from here - the function `PosEx()` in [[Unit\|unit]] StrUtils is perfect for this purpose:
37	+
38	+	``` pas
39	+	uses
40	+	StrUtils;
41	+
42	+	type
43	+	TForm1 = class(TForm)
44	+	private
45	+	FFoundPos: Integer;
46	+	...
47	+
48	+	procedure TForm1.Button1Click(Sender: TObject);
49	+	begin
50	+	with FindDialog1 do
51	+	begin
52	+	if frEntireScope in Options then // Search begins at file start
53	+	FFoundPos := 0
54	+	else
55	+	FFoundPos := Memo1.SelStart; // Serach begins at current cursor position
56	+	Execute;
57	+	end;
58	+	end;
59	+
60	+	procedure TForm1.FindDialog1Find(Sender: TObject);
61	+	begin
62	+	with Sender as TFindDialog do
63	+	begin
64	+	FFoundPos := PosEx(FindText, Memo1.Lines.Text, FFoundPos+1);
65	+	if FFoundPos > 0 then
66	+	begin
67	+	Memo1.SelStart := FFoundPos - 1;
68	+	Memo1.SelLength := Length(FindText);
69	+	Memo1.SetFocus; // Memo1 must be activated, otherwise the selection effect will not be displayed
70	+	end else
71	+	Beep();
72	+	end;
73	+	end;
74	+	```
75	+
76	+	## See also
77	+
78	+	- [[doc:lcl/dialogs/tfinddialog.html\|TFindDialog doc]]
79	+	- [[TReplaceDialog]]
80	+
81	+	---
82	+	From the Free Pascal wiki, page "TFindDialog", as it stood on 2020-05-01 after a change by TyphonFinger, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).

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