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Visual Studio86
Hi all !



VB.NET adds the ability to create variables that are visible only within

a block. A block is any section of code that ends with one of the words

End , Loop , or Next . This

means that For...Next and If...End If blocks can have their own

variables.



So,



While y>6

Dim x as interger

......

End while



But x have lifetime of procedure level. Means,

Dim x as interger -- This line geting eff. at first time only. is it

right ?





Thanks & Regards



Elankathir,

B'lore,

India.



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if you are asking how to use vars in loops i would say

(pseudo)

private sub bla

dim x as object

loop

x = new object

end loop

end sub



local in a for could also be



for i as integer = 0 to 100 step 1

array(i). bla = bla

next i



yust some thoughts



eric



"ElanKathir .S.N" <elankathirctech@yahoo.co.in>wrote in message



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Hi Elan,



Yes and they overrule the variables declared on a higher level outside the

method.



However you can not declare variables more times inside a method



It is in every block too every block from a try catch error block by

instance.



I hope this helps?



Cor





-

Elankathir and everybody else,



Here's a sample:



Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As

System.EventArgs) Handles Button1.Click

Dim i As Short

For i = 1 To 10

Dim x As Short

x = 1

Next

Dim x As Short

MessageBox.Show("x = " & x)

End Sub



As shown, I get an error at the first declaration of x, saying that x hides

a variable declared in the enclosing block. This is interesting, since the

declaration is after the For loop. This appears to show that all

declarations happen before any code in a block is executed, regardless of

where the Dim statements are. Is that correct?



When I comment out the second declaration, I get an error in the message box

line saying that x is not accessible in this context because it is private.

It cannot be changed to protected or public.



I haven't tried it, but I'm pretty durn sure that in C++, a similar

construct would be perfectly acceptable. The inner x would be used in the

for loop, and the message box would show a random value because the outer x

would never have been initialized. There is no check for whether a variable

declaration in one scope hides a declaration in another scope. At most, a

warning, not an error, would have been generated.



I tried commenting out the inner declaration and leaving the outer

declaration. I got an error saying that x cannot be used before it is

declared.



Ah, well. This doesn't seem to be an issue I'm going to need to worry about

much in real life.



Rob





-

Seeing the message from Rob, I see I did not write it clear (I did want to

simplivy it)



I made a mistake in my message I see when I see your message, this is

allowed



for i as integer = 0 to 100

dim x =1

next

for i as integer = 0 to 100

dim x = 1

next



however this

dim x as integer

for i as integer = 0 to 100

dim x =1

next

for i as integer = 0 to 100

dim x = 1

next

will give an error



Cor









-

"Cor Ligthert" <notfirstname@planet.nl>schrieb

Sorry Cor, but I really don't understand the last sentence. What do you

mean? Maybe the OP understands it but I'm really also interested.





--

Armin



-

Hi Armin,



I saw too this was a very quick written message.



Catch, End Try block.



I hope this makes it even without the rest of the text more clear?



(I do not know why I write the last days try catch error block, now i see I

have to watch for that, I did that more times)



Thanks for making me attent on this



Cor





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"Cor Ligthert" <notfirstname@planet.nl>schrieb

Now I understand. Your "too" was confusing me. :-)



"I saw (that) this was a very quickly written message, too."

"I also saw (that) this was a very quickly written message."



:-))



(I really hope that this is correct *g*)





Sorry for correcting you, but I think this is allowed on Fridays at this

time (you (and everybody else) can correct me, too). ;-)))) The time should

be at the start or end of the sentence.



"I do not know why I write try catch error block (in) the last(past?) days,

now i see I have to watch for that, I did that many times"



Should only be a little hint because I'm often sitting in front of your

messages a long time. :-))) But don't care about me as long as everybody

else understands you. ;-)





--

Armin



-

However let us not do to much correction in this sense, we loose it anytime

from a lot of others here.



:-))



Cor





-

"Cor Ligthert" <notfirstname@planet.nl>schrieb

Sorry, I don't understand you. ;-))





--

Armin



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