Lazarus
Home
Help
TinyPortal
Search
Login
Register
Lazarus
»
Forum
»
Free Pascal
»
General
(Moderators:
FPK
,
Tomas Hajny
) »
[SOLVED] „Error: Constant and CASE types do not match‟ with string
Free Pascal
Website
Downloads
Wiki
Documentation
Bugtracker
Mailing List
Lazarus
Website
Downloads (Laz+FPC)
Packages (OPM)
FAQ
Wiki
Documentation (RTL/FCL/LCL)
Bugtracker
CCR Bugs
IRC channel
GIT
Mailing List
Other languages
Foundation
Website
Useful Wiki Links
Project Roadmap
Getting the Source
Screenshots
How to use the forum
About donations (wiki)
Bookstore
Computer Math and Games in Pascal
(preview)
Lazarus Handbook
Search
Advanced search
Recent
Database standards OR Am ...
by
egsuh
[
Today
at 08:56:31 am]
FpDebug unexpected Assemb...
by
Marc
[
Today
at 08:46:38 am]
Who is Indy mattias?
by
jollytall
[
Today
at 08:26:24 am]
How to: create DLL file f...
by
KodeZwerg
[
Today
at 08:17:30 am]
Step-into the field sette...
by
ginoo
[
Today
at 08:11:29 am]
Offical launch of the 1 B...
by
Handoko
[
Today
at 07:59:07 am]
Big Numbers Math
by
iLya2IK
[
Today
at 07:13:20 am]
Lazarus for Windows on aa...
by
dbannon
[
Today
at 07:02:55 am]
BUG REPORT: Unable to gen...
by
dbannon
[
Today
at 06:29:49 am]
what to do if my target M...
by
Laksen
[
Today
at 12:49:12 am]
For-in loop over constant...
by
ASerge
[
Today
at 12:36:09 am]
Converting a string/index...
by
TRon
[April 18, 2024, 11:56:37 pm]
exclude ALL packages from...
by
PascalDragon
[April 18, 2024, 11:33:29 pm]
Demoscene The Champs Crac...
by
KodeZwerg
[April 18, 2024, 11:29:50 pm]
Poll: Watches and Display...
by
440bx
[April 18, 2024, 10:55:14 pm]
Have anyone develop UEFI ...
by
PascalDragon
[April 18, 2024, 10:14:15 pm]
The weird Rewrite bug
by
PascalDragon
[April 18, 2024, 09:58:53 pm]
Assign (textfile) not com...
by
PascalDragon
[April 18, 2024, 09:51:50 pm]
Question for people who h...
by
PascalDragon
[April 18, 2024, 09:44:32 pm]
Linux Workspaces -- StayO...
by
AmatCoder
[April 18, 2024, 08:34:20 pm]
I just released a commerc...
by
Seenkao
[April 18, 2024, 07:57:21 pm]
Access violation when re-...
by
TRon
[April 18, 2024, 07:37:31 pm]
[SOLVED] assembler name i...
by
TRon
[April 18, 2024, 07:26:33 pm]
A fairly simple sound sol...
by
KodeZwerg
[April 18, 2024, 07:01:52 pm]
[Fun Fact] PNG and Micros...
by
Ten_Mile_Hike
[April 18, 2024, 06:24:19 pm]
« previous
next »
Print
Pages: [
1
]
Author
Topic: [SOLVED] „Error: Constant and CASE types do not match‟ with string (Read 8923 times)
CM630
Hero Member
Posts: 1091
Не съм сигурен, че те разбирам.
[SOLVED] „Error: Constant and CASE types do not match‟ with string
«
on:
July 09, 2018, 03:31:48 pm »
Following code works right:
Code: Pascal
[Select]
[+]
[-]
procedure
TForm1
.
Button1Click
(
Sender
:
TObject
)
;
var
A
:
string
=
''
;
B
:
string
=
'B'
;
C
:
string
=
'C'
;
begin
A
:
=
B
;
case
A
of
'B'
:
ShowMessage
(
B
)
;
'C'
:
ShowMessage
(
C
)
;
end
;
end
;
But this code generates „Error: Constant and CASE types do not match‟.
Code: Pascal
[Select]
[+]
[-]
procedure
TForm1
.
Button1Click
(
Sender
:
TObject
)
;
var
A
:
string
=
''
;
B
:
string
=
'B'
;
C
:
string
=
'C'
;
begin
A
:
=
B
;
case
A
of
B
:
ShowMessage
(
B
)
;
C
:
ShowMessage
(
C
)
;
end
;
end
;
B and C are strings. I tryed to cast to cast them to strings, anyway, but still I get the same error?
Is it me doing sth. wrong?
«
Last Edit: July 09, 2018, 04:00:45 pm by CM630
»
Logged
Лазар 3,2 32 bit (sometimes 64 bit); FPC3,2,2; rev: Lazarus_3_0 on Win10 64bit.
RayoGlauco
Full Member
Posts: 179
Beers: 1567
Re: „Error: Constant and CASE types do not match‟ with string
«
Reply #1 on:
July 09, 2018, 03:49:09 pm »
In the second example, you use variables as selectors, instead of constants (B is a variable; 'B' is a constant). You cannot use variables as selectors.
See
http://wiki.freepascal.org/Case
Logged
To err is human, but to really mess things up, you need a computer.
Thaddy
Hero Member
Posts: 14373
Sensorship about opinions does not belong here.
Re: „Error: Constant and CASE types do not match‟ with string
«
Reply #2 on:
July 09, 2018, 03:50:04 pm »
Needs a literal value, indeed.
Logged
Object Pascal programmers should get rid of their "component fetish" especially with the non-visuals.
Gammatester
Jr. Member
Posts: 69
Re: „Error: Constant and CASE types do not match‟ with string
«
Reply #3 on:
July 09, 2018, 03:50:20 pm »
You should read the second part of the error message 'Error: String expression expected'. The case labels must be constants (i.e. literals or true constants). Your construct would throw equivalent message even for integer variables. The following code does work:
Code: Pascal
[Select]
[+]
[-]
var
A
:
string
=
''
;
const
B
=
'B'
;
C
=
'C'
;
begin
A
:
=
B
;
case
A
of
B
:
writeln
(
B
)
;
C
:
writeln
(
C
)
;
end
;
end
;
Logged
CM630
Hero Member
Posts: 1091
Не съм сигурен, че те разбирам.
Re: „Error: Constant and CASE types do not match‟ with string
«
Reply #4 on:
July 09, 2018, 03:57:15 pm »
Ok, thanks, I will rewrite it with
Quote
If... then.
Logged
Лазар 3,2 32 bit (sometimes 64 bit); FPC3,2,2; rev: Lazarus_3_0 on Win10 64bit.
Print
Pages: [
1
]
« previous
next »
Lazarus
»
Forum
»
Free Pascal
»
General
(Moderators:
FPK
,
Tomas Hajny
) »
[SOLVED] „Error: Constant and CASE types do not match‟ with string
TinyPortal
© 2005-2018