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switch-statement ???

Hi,

can you specify a range in a switch - statement ?

switch (i)
{
case 100 - 999 :
// do something
break;
case 1000 - 9999:
// do something else
break;
}

Previous syntax is not allowed, I know,
but can you solve this using 'switch' ? without having to provide a case
statement for every possible value and without using 'if' ?

thanks
Christian

Nov 16 '05
14 2359
in vb we used this technique a lot its neat

switch(true)

{case (10 < 100):

MessageBox.Show ("First ");

break;

case (10> 100):

MessageBox.Show ("Second");

break;

default:

MessageBox.Show ("default");

break;

}
substitute variable in place of 10

hth
ambrish

"Paul E Collins" <fi************ ******@CL4.org> wrote in message
news:ck******** **@sparta.btint ernet.com...
"Chris" <ch********@pan dora.be> wrote:
switch (i)
{
case 100 - 999 :


That will actually compile, but it won't do what you want. (The minus sign
is subtraction, so it's equivalent to "case -899".)

You can't specify ranges in a C# switch statement.

P.

Nov 16 '05 #11
LOL - I must have been in phonetic mode ;-)

Regards

Richard Blewett - DevelopMentor
http://staff.develop.com/richardb/weblog

nntp://news.microsoft. com/microsoft.publi c.dotnet.langua ges.csharp/<On************ **@TK2MSFTNGP14 .phx.gbl>
Also you are aloud to


should be "allowed to"

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[microsoft.publi c.dotnet.langua ges.csharp]
Nov 16 '05 #12
ambshah <am*****@hotmal e.not4spam> wrote:
in vb we used this technique a lot its neat


Is that any better than:

if (i < 100)
{
....
}
else if (i > 100)
{
}

though?

If so, why?

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Nov 16 '05 #13
"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote:
Is [VB's Case x To y] any better than
[if i ... else if i ...]
If so, why?


Well, I'll play devil's advocate: the 'if - else if' form makes you
repeatedly specify the variable being tested, which could lead to an
obscure bug if you accidentally specify a different variable at some
point.

P.
Nov 16 '05 #14

"Paul E Collins" <fi************ ******@CL4.org> wrote in message
news:ck******** **@hercules.bti nternet.com...
"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote:
Is [VB's Case x To y] any better than
[if i ... else if i ...]
If so, why?


Well, I'll play devil's advocate: the 'if - else if' form makes you
repeatedly specify the variable being tested, which could lead to an
obscure bug if you accidentally specify a different variable at some
point.

P.


On the other hand, if you have the variable mentioned on the top of the
switch and then you have 20 cases spread along four pages of code, you might
just wonder what your case 10-100: means.

Personally, I think that ranged cases allow for more bugs than multiple
if's.

Stefan
Nov 16 '05 #15

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