C# Form Close

[Storm33229]

Ok, I am using Visual Studio 2k5 Express Edition...
Now, if you've ever used it, you'll know it generates Form code VERY cleanly. This aside, I have the 'Start' Form that starts up from Main.
Then I have a button that leads to Form2. This button is supposed to:
-Close(not hide) the Start Form.
-Create a new instance of Form2.
Code? I tried[in start as the button is in that form]:

Form2 ff = new Form2();
ff.Show();
this.Close();

Then it compiled fine... but the button closed both the forms upon clicking.

-Storm

[swtrse]

Well since Form1 is your mainform you cannot close it without closing the application. Thats the reason why both forms are closed. Even if you do not define Form1 as the parent form for Form2.

So you only can hide Form1.
The reason can be found in the hidden part of the partitial class of Form1.
Ther should be some line like.

void main()
{
Application.Run(new Form1());
}

[Jeff]

Form2 ff = new Form2();
ff.Show();
this.Hidden = true;

try that

[Sep102]

Originally Posted by Sorious

Form2 ff = new Form2();
ff.Show();
this.Hidden = true;

try that

This would work but isn't what he said he wanted,

Originally Posted by Storm33229

-Close(not hide) the Start Form.

Now, what could be done to do this is to only have a this.Close(); statement in the Button's OnClick, then have Application.Run(new Form2()); in the Main() method after the Application.Run(new Form1());

Of course, some trickery would need to be involved if you wanted this to happen only when the Button is used and not when the form is closed in some other way, but this is a (hackish) way to do this.

[Storm33229]

ok but if I hide it and I have a "Back" button, then i dont want to create a new instance of Form1.

[mordero]

then the back button could just close/hide the second form and make Form1 visible...

[swtrse]

Originally Posted by Sep102

Now, what could be done to do this is to only have a this.Close(); statement in the Button's OnClick, then have Application.Run(new Form2()); in the Main() method after the Application.Run(new Form1());

Of course, some trickery would need to be involved if you wanted this to happen only when the Button is used and not when the form is closed in some other way, but this is a (hackish) way to do this.

It's not recommendet to manualy change code generated by designers, because the designers changes the code back sometimes.

Well since you only do not want to not make a new instance why not call Form2 as a modal dialog with that code (pseudocode)

funktion showmeForm2()
{
    HideForm1();
    ShowModalDialog(Form2);
    UnhideForm1();
}

This way if you call Form2.Close() within Form2, Form1 will automatically reapier without creating a new instance.

Since If you want to hide/clode Form1 I see no need to use an unmodal dialog.

[Sep102]

Originally Posted by swtrse

It's not recommendet to manualy change code generated by designers, because the designers changes the code back sometimes.

Really, if you want to be fair about that statement, you shouldn't be changing any of the code for the class it derives for you from the Form class to represent your GUI, since that's also all generated code (especially before, when there were no partial classes, whew, scary). Also, as far as I know, none of the code in the Main method are ever generated or modified by the designer, only the code that actually has to do with GUI that the designer is editing.

Its parts that are not marked as being designer generated code most likely have about as much chance of being arbitrarily changed by the designer as the Main method does (note that I'm talking about logic, not about the identifiers). The only parts that one would really have to worry about being changed would be the code in the (FileName).Designer.cs part that (FileName).cs is split into, and even in that the code that is routinely changed is marked off by a region (except for the field declarations).

Anyways, I never once said I would recommend doing it that way, only that it was a way that could accomplish what he wanted in some fashion, I even acknowledged that it was a hackish way to do it, I was just presented some form of a solution that met his restrictions in his first post.

[swtrse]

Wellwtih designer generated code I was refering to
.NET 1.0+1.1: the region within the generated class telling you that this is gernerated code and should not be changed.
.NET 2.0: parts of partitial classes or clases marked with the GeneratedCodeAttribute.

Hope that makes it clear.

[Sep102]

Originally Posted by swtrse

Wellwtih designer generated code I was refering to
.NET 1.0+1.1: the region within the generated class telling you that this is gernerated code and should not be changed.
.NET 2.0: parts of partitial classes or clases marked with the GeneratedCodeAttribute.

Hope that makes it clear.

Neither of which contains the Main method, which is where I was talking about changing, I just wanted to point that out as you seemed to be saying that it would be wrong to edit it as the designer would possible change it. This was all that I was attempting to point out. Perhaps you just meant it as a general guide earlier when you stated that you should not change the designer generated code? Unless of course you were talking about my use of the Button's OnClick method, however that is not part of the code that the designer changes and is not marked.