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I've got a VB .NET Web application that has several frames (for discussion

sake, let's call them Form1.aspx and Form2.aspx). I want to be able to call

a code module in Form2.aspx.vb from code module in Form1.aspx.vb. How do I

format this statement?

I'm not interested in calling client-side script on Form2.aspx from

Form1.aspx.vb - I want to fire off server-side module in Form2.aspx.vb


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A Standard Module is part of the server side compilation, and provides a more

reliable place to store commonly used functions. Since a page is

instantiated, it may or may not exist. Page methods are not, to the best of

my knowledge, accessible between pages. The Session is a good place to

store objects that maintain state. You can create an object through a class

module, and store and retrieve that object through a Session variable.

Session variables are available to various pages of a single Session.



"johnf401" wrote:

John,



In addition to Charlie,



You cannot call a method in form1 from form2.



Every form is stateless, which means that when it loads it start everytime

again new.



As Charlie stated, you can pass information between forms. There are more

methods for that, however all will in my opinion probably fail in your

situtation except the already by Charlie suggested Session.



Just a little addition.



Cor





"johnf401" <johnf401@discussions.microsoft.com>





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On 2004-10-30, Charlie <Charlie@discussions.microsoft.com>wrote:

No, there's nothing special about code-behind modules, they're just

regular classes.



To call a non-shared function inside Form2.aspx.vb, instantiate the

class and call the function. The fact that it's in an aspx.vb as opposed

to simply a .vb file is irrelevant.



Dim frm as New Form2

frm.SomeFunction()



BTW, I do agree that doing this represents a pretty bad design, and it's

much better to move the common code into a "standard" class. Also,

performance will be worse than it should be, since code-behind classes

are fairly heavy since they derive from Page. But there's no technical

reason stopping one from doing this.

David,



Technicaly you are right, however what is the sense of instansing a complete

New form in or windowsforms or webforms for using a method in that.



By stating as you do people can get the idea that it is possible in Webforms

as it is as well in Windowforms to reference an already used form class

(with setted information), what is in my opinion in a webform impossible,

while it is easy possible in a winform when you pass the sending form (the

one which was first) in an overloaded Sub New to the let say form2. (Not

nice code by the way).



Just my thought,



Cor







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On 2004-10-31, Cor Ligthert <notmyfirstname@planet.nl>wrote:

I quite plainly said it was a bad design.



Perhaps, but I think it's important to be clear about what is

technically impossible and what is really bad design. I was more

focused on correcting the errors in the previous post (not your post),

so perhaps I should do that explicitly.



"Standard Module is part of the server side compilation"



This is true of the code-behind class as well.



"Since a page is instantiated, it may or may not exist."



This is true of any class. It's not true of a VB.Net Code Module, nor

would it be true if the first Form used shared functions.



"Page methods are not, to the best of my knowledge, accessible between pages. "



They are. Methods in Page-derived classes are just as accessible as a

method in any other class. The class is just a bit top-heavy for

regular use.



Anyway, I suppose we should help the original poster a little more

directly, so in response to the top of the thread.



The fact that two forms load as frames on a single page is totally

irrelevant to ASP.Net. The two forms load as two individual page

requests, just as they would if the two pages weren't in a frame at all.

There's no way for one page request to reference another page request,

except by using things like the Session object as has been suggested.



Also, keep in mind that frames don't necessarily load in order. So if

you want Form2 to reference a session variable that Form1 has set, then

you'll have to do something special to ensure that Form1 is loaded

first. (This one will bite you, because *usually* the frames will load

in order, especially when debugging locally).





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David,



Very nice message,



I stuffed the part in my messaged where I wrote that you had stated it as

bad code, because for me that was included in my sentence that you are

technicaly right..



Cor



"David" <dfoster@woofix.local.dom>

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