TFileStream: what changed

Revision 0 to 1. Removed lines have a minus sign; added lines have a plus sign.

Title: TFileStream

New		Line
1	+	A TFileStream is a descendant of [[TStream]] that gets/stores its data from/to a file on disk.
2	+
3	+	\| Constant \| Decimal \| Description \|
4	+	\|------------------\|---------\|--------------------------------------------\|
5	+	\| fmCreate \| 65280 \| Creates a new file \|
6	+	\| fmOpenRead \| 0 \| opens a file for reading \|
7	+	\| fmOpenWrite \| 1 \| opens a file for writing \|
8	+	\| fmOpenReadWrite \| 2 \| opens a file for reading and writing \|
9	+	\| fmShareDenyWrite \| 32 \| prohibit writing if file is already opened \|
10	+
11	+	- read entire file fnam into a string.
12	+
13	+	``` pascal
14	+	function readstream(fnam: string): string;
15	+	var
16	+	strm: TFileStream;
17	+	n: longint;
18	+	txt: string;
19	+	begin
20	+	txt := '';
21	+	strm := TFileStream.Create(fnam, fmOpenRead or fmShareDenyWrite);
22	+	try
23	+	n := strm.Size;
24	+	SetLength(txt, n);
25	+	strm.Read(txt[1], n);
26	+	finally
27	+	strm.Free;
28	+	end;
29	+	result := txt;
30	+	end;
31	+	```
32	+
33	+	- read 8 bytes of fnam into a byte array:
34	+
35	+	``` pascal
36	+	..
37	+	type
38	+	TByte8Array = array [0..7] of byte;
39	+	..
40	+	function readstream(fnam: string; position= integer): TByte8Array;
41	+	var
42	+	strm : TFileStream;
43	+	begin
44	+	strm := TFileStream.Create(fnam, fmOpenRead or fmShareDenyWrite);
45	+	try
46	+	strm.Position:=position;
47	+	strm.Read (Result[0],8);
48	+	finally
49	+	strm.Free;
50	+	end;
51	+	end;
52	+	```
53	+
54	+	- Write a string txt to the file fnam.
55	+
56	+	``` pascal
57	+	procedure writestream(fnam: string; txt: string);
58	+	var
59	+	strm: TFileStream;
60	+	n: longint;
61	+	begin
62	+	strm := TFileStream.Create(fnam, fmCreate);
63	+	n := Length(txt);
64	+	try
65	+	strm.Position := 0;
66	+	strm.Write(txt[1], n);
67	+	finally
68	+	strm.Free;
69	+	end;
70	+	end;
71	+	```
72	+
73	+	## See also
74	+
75	+	- [[File types]]
76	+	- [[doc:rtl/classes/tfilestream.html\|TFileStream doc]]
77	+	- [[doc:rtl/classes/tstream.html\|TStream doc]]
78	+
79	+	---
80	+	From the Free Pascal wiki, page "TFileStream", as it stood on 2022-04-12 after a change by Bart, 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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