Question Opening Childform creates new instance of ParentForm

[deanobravo]

Hi,
I am very new to VB.net (like 2 days in) and am in the process of upgrading a VB6 Project to Vb.net.
My problem is that when I open a child form in my project from within the Parent form a new instance of the Parent form is created.
The code is fairly simple:

frmnewContract.MdiParent = Me
frmnewContract.Show()

Any help appreciated.
Thanks.

 

[deanobravo]

I think I may have found a partial answer to this. My program started through Sub Main, I have now amended it to start via the Login Screen which has allowed me to select "make single instance application" as part of my Application's Properties. This has resolved the problem, however, I would still like to know why this was happening purely for my own edification. I created a small test application with a couple of forms and a sub main and I couldn't get it to replicate the re-instancing.

 

[jmcilhinney]

I can't see anything in that code that would cause that issue. I can only assume that there was something corrupted in your original project.

 

[deanobravo]

Yeah, I thought maybe the upgrade wizard had done something behind the scenes that i'm too new to see.
Cheers mate.