Passing integer value between forms

[PlayKid]

Hi all,

 

I am having 2 forms, and I have declared an integer variable in form 1, then I assign something from from2 to that integer value, but it just didnt pass my value, can somebody tell me why??But when I am passing a textbox value, it can be passed.

 

PlayKid

[neodammer]

One way to do it is just add a module to the project and declare the variables there publicly.

[IceAzul]

Difference between Reference and Value types

http://msdn.microsoft.com/msdnmag/issues/1200/dotnet/

[Nerseus]

@PlayKid, Maybe you could show us some code snippets of what you're doing? You describe Form2 referencing a variable on Form1 and I'm curious how you've set this up - it will get you a better answer if we know the full picture of what you're doing. Include anything you may have tried, whether it worked or not, as that may help us understand as well.

 

-ner

[vbMarkO]

It was mentioned already, but thought I might add..

 

Create a Module and in the module declare the variable you wish to pass with

make it public

 

Public myInt As Integer ' This would go into the module

 

 

Then in Form1 you could assign something to the variable

 

myInt = "123" ' in Form1

 

then in Form2

 

intLBL.Text = myInt ' Result in the label would be 123

 

vbMarkO

[PlausiblyDamp]

Modules are not a particularly OO way to approach the problem - what happens if you have several forms that 'share' information this way? Sooner or later you will end up introducing bugs.

For a better approach to passing information between forms etc you may want to give clicky a read.

Edited September 8, 2005 by PlausiblyDamp

[PlayKid]

Thanks for all of your replies, here is my code.

In Form 1:

   Private Sub MorepersonButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MorepersonButton.Click
       Dim MDIChildMCPersons As New MCPersons
       MCPersons.SupplierNumber = 2
       MDIChildMCPersons.MdiParent = ParentForm
       MDIChildMCPersons.Show()
   End Sub

 

In Form2:

Public Shared SupplierNumber As Integer

   Private Sub MCPersons_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
       Label1.Text = SupplierNumber.ToString
   End Sub

 

And it doesn't doing good. The result is 0 instead of 2.

[PlausiblyDamp]

Firstly is there a reason why you declared SupplierNumber as shared? It probably isn't required or offering any real benefit in this case.

If you step through the code in a debugger is SupplierNumber actually being assigned to correctly?

[PlayKid]

This is one of my method, another method is without the shared, still either ways, they still not working.

Is there something wrong with my code?

[PlausiblyDamp]

Did you try stepping through in a debugger to see what happens? Have you tried it without the shared keyword and stepped through the relevant code?

 

Also rather than just using a public variable have you trioed using a property instead and placing a breakpoint within the property set to see if it is getting called correctly?

[PlayKid]

Yes, I did, but when I clicked the form, the debugger is not responding, what can I do?

[Souma]

In the first form, u declare

 

' This is the variable u wanted to be used by other form(s)
Public Shared myVal as Integer

 

In the next/other form(s), u need to have the following

 

' So that u can use the variable u declared in first form
Dim firstfrm as new FirstForm

firstfrm.myVal = 2

[PlausiblyDamp]

It would be a lot easier if you posted a more complete code sample like Nerseus suggested earlier.

I would definately argue against all the suggestions to use shared / module level variables as a way to pass information between forms.