How to return the name of a tab at a particular index?

[Alex Dransfield]

I want to set a tab page to null and I have the index of the tab page. Is there a way I can get the name of a tab at an index, or even better address the tab by its index so I could, for example, say (NOT CODE) TabPage[tabIndex] = null; ?

if (tabControl1.TabCount == 1)
            {
                MessageBox.Show("Unable to close the last tab, please open another tab before attempting to close this one.");
            }
            else
            {
                int currentlySelelected = (Convert.ToInt32(tabControl1.SelectedIndex));
                tabControl1.TabPages.RemoveAt(currentlySelelected);
                tabControl1.TabPages[currentlySelelected] = null;
            }

Trying to use something like this but either the tab is removed so I can't null it, or it's nulled so I can't remove it. Not sure how to overcome this.

[GaryTexmo]

You don't need to null it... per se. When you remove it from the tab control, it's no in the TabPages collection. Assuming nothing else references it, the garbage collector will eventually get rid of it.

That said, yes you can still do this. You're trying to set something to null that no longer exists in the collection. It's simple enough to fix this, just create a TabPage object and have it be a reference to the one you want to destroy.

TabPage destroyMe = tabControl1.TabPages[currentlySelected];
tabControl1.TabPages.RemoveAt(currentlySelected);
destroyMe.Dispose();

Still, anything else that refers to that particular tab page will still be trying to access it, but at least it will be in the disposed state now, helping you figure out where that might be.

Again though, this really isn't necessary as long as you're not keeping multiple references to your tab pages. Once you remove them, they're gone and you can't get them back.

[Alex Dransfield]

It's bad programming, but to ensure that the tab can't be opened multiple times I do a if(DesignTab != null), and if it's null I go on to create it. I'm not aware of a "already exists" check.

[GaryTexmo]

I don't really know the details of what you're trying to do, but if you've got two tabs you should be able to compare them. Can you provide more details about what you're trying to do? I'm not sure what to suggest here because I don't know the context.

[Alex Dransfield]

Well I can have any number (>1) of tabs at any one time. I want to make it so that the user can only open one instance of a particular tab at any one time. How would I use the comparison?

Thanks for all your help by the way, I'm learning as I go along.

[Alex Dransfield]

I seem to have done what I was out to achieve. Thanks for your help Gary :)

[GaryTexmo]

I'm not sure if you can compare them directly... a simple test will tell you if you can :)

TabPage p1 = tabControl1.TabPages[0];
TabPage p2 = tabControl1.TabPages[0];
 
if (p1 == p2) MessageBox.Show("Equal!");

I'm actually thinking you can't do that, it's going to try to compare the references and come out not equal... but it's worth trying.

If that doesn't work, you can always give your tab pages unique names...

TabPage firstPage = new TabPage();
firstPage.Name = "first page";
 
TabPage secondPage = new TabPage();
secondPage.Name = "second page";
 
tabControl1.TabPages.Add(firstPage);
tabControl1.TabPages.Add(secondPage);

Now, with a slightly modified version of the above...

TabPage p1 = tabControl1.TabPages[0];
TabPage p2 = tabControl1.TabPages[0];
 
if (p1.Name == p2.Name) MessageBox.Show("Equal!");

... You should get a valid test.

(Assuming you still need that... you mentioned you got it figured out, but I figured I'd follow up anyway :D)

[Plater]

I would say it is a better plan to do this:

TabPage destroyMe = tabControl1.TabPages[currentlySelected]; 
tabControl1.TabPages.Remove(destroyMe); 
destroyMe.Dispose(); 
 

[GaryTexmo]

Actually, I agree. That would also imply that the first test above is sufficient... curiosity has gnawed at me long enough, so I'm going to sneak into VS and verify it...

... and it does! Which now that I think about it... duh. I think I was hung up on old C++ syntax and now I'm a bit red in the face.