Develop Reference

Multi form Projects in c# - Displaying multiple windows

My main form is this
Now my problem occurs when I click Add -> Student, which is meant to bring up a new window that, instead it does this
So as you can see it opens the new form inside the same window. It didn't use to do this, then I made the main form an MdiContainer and set it as the MdiParent of the second form.
Is there a property I can change to make this new form pop up in a new window? Becuase I need to leave the MdiContainer property as True so that I can take data from Form2 and use it in Form1
Please let me know any other information you may need to help me fix this issue, as I'm not sure what caused it so I don't know what to change in order to fix it or even where I'm meant to be looking

you need to hide form enroll
when you open add window add.show()
you need to hide enroll form enroll.hide()

Add a form to a MDI child

In Form1 I'm enabling IsMdiContainer and I added a MenuStrip. In Form1_Load I "new" Form2 and I'm assiging Form2.MdiParent to this which is Form1. I'm also maximizing Form2 and this operation works well.
In Form2 I have a treeView on the left side of the form and on the right side of the form I would like to display a number of different forms with various editing capabilities which will be dependent upon the node or level selected in the treeView.
I would like to create a number of different forms for editing data that would be displayed in Form2 depending on the selection from the treeView. I can't seem to add a form to the MdiChild and I've been seeing some posts where adding a form to a form may create some programming problems which I'm not sure about.
I really don't have any code to paste into this post because nothing seemed to work except for the Mdi Parent and Child relationship which was pretty simple.
Thanks in advance for any help.

There is a lot of information on this subject, but some documentation can be difficult to understand for some new developers. Follow these steps:
Open Visual Studio
Create a Windows Form Application
Click your Form
Go to Properties for that Form
Minimum Size : 1366 pixels by 768 pixels.
Launch Maximized
The important element is IsMdiContainer
Open your Toolbox.
Go to Menus
Drag FileMenu onto your Form
Build your Menu
Then go to Solution Explorer
Right-Click Add Item
Add another Form
I left mine as Form2 (In a real program, not a good name).
So within those fifteen steps, we have all that we need to accomplish our goal. So what we will do to finish our task is:
Go back to our First Form
Go to our FileMenu
Double Click on the menu button you wish to link.
It will load a code view, inside the area put this:
Form2 newFrm = new Form2();
newFrm.MdiParent = this;
newFrm.Show();
What this code is doing is three distinct things:
Line 1: It is actually calling our object, in this case a second form. It is actually building our object for us.
Line 2: Is actually linking our second form to our current form, this is physically turning our second form into a Child Form.
Line 3: This is actually physically showing our second form when the button is clicked.
That is all you need to physically show a Form.
In regards to your second question, I'm not entirely sure what your attempting to accomplish. It sounds like your trying to have a tree, then as a Node is selected the right hand side of the Form changes to specific context.
Now this isn't the nicest example, but do you mean something like this?
TreeNode node = treeView1.SelectedNode;
if (node.Text.Contains("XP"))
{
TextBox one = new TextBox();
Panel i = new Panel();
i.Dock = DockStyle.Right;
i.BackColor = Color.Black;
i.Controls.Add(one);
i.Show();
TreeFrm.ActiveForm.Controls.Add(i);
}
Not sure if that is what you are seeking. Obviously you'd want to implement a FlowLayoutPanel to make the positioning not a pain for you. Keep in mind an MDI Parent, with a Child Form acting as a MDI Parent will not work very well. As most things will default to MDI Parent Forms Docking / Positioning. This example is not pretty, but I'm not entirely sure of what your asking.
Are you trying to dock other forms or components on the same form?

Form losing focus in c#

I have a main form, which opens form A, where from form A I can open form B, where from form B I can open form C. The problem is that if I open till form B, everything works fine, but if I open form C as well, and then close Form C and B, form A goes behind the main form. For the forms I m just creating an instance of the form and then use .Show()
cNewForm form = new cNewForm();
form.Show();
I m doing this for every form

You have not set the window ownership properly because you are using the no parameter version of Show(). You need to set the owner by calling the Show() overload that receives an owner parameter. Alternatively you can set the Owner property directly, but it's much better to do so when you call Show().
The window owner is an important Win32 concept. I recommend reading the MSDN documentation on the subject.
An owned window is always above its owner in the z-order.
The system automatically destroys an owned window when its owner is destroyed.
An owned window is hidden when its owner is minimized.
In your case I think you want form A to be owned by your main form, and form B to be owned by form A, and form C to be owned by form B.

I have often found that these kinds of issues are resolved by assigning owners to windows. When you show the window:
FormA formA = new FormA();
formA.Show(this); // assuming this code is in the main form

try to use the ShowDialog(); methode instead of show() in order to show it as a modal form. see the documentation

parent form is accessible when child form is open

I have created a parent form and a child form in c# when i click a menu item in parent form, it opens the child form but still i access the parent form.i want that the parent form will remain inaccesible until the child form is open.please send me the code.thnks

try with this
form.ShowDialog()

Probably you should use form.ShowDialog() method instead of form.Show()
Definitely you should add a better description, at least framework you are using (WinForms?). C# is not a framework.

Use, form.Hide() process to make the Parent form to be not accessable when ever the child form opens and again give form.show() to activate the parent form.

If you want your parent form visible while showing your child form then you can do following.
form.ShowDialog(this).
Where this is the instance of your parent form.
On the other hand, if you want your parent form hide while showing child form you can do following
this.Hide();
form.ShowDialog(this)

How do you make a non-modal topmost dialog that is only topmost in regards to the parent form in WinForms?

Thinking about this for an About dialog but I'm sure it's applicable in other places (say a find box)
Sorry if this is a dupe, but I couldn't find this or how to articulate the last part about it only being on top of the parent. How do you make a form that is always on top of the parent form, but is non-modal, but doesn't cover up other apps?

Try this to open your dialog:
FindDialog fd = new FindDialog();
fd.Show(this);
The key is to assign dialog's owner.

Not sure exactly what you mean; Form.ShowDialog is only modal with respect to the parent, not the application, unless the application is single threaded.
For example, I made an app to test this which was organized like the following:
mainform:
2 buttons, each of which begins a thread that creates a frmDialog1 and calls ShowDialog
frmDialog1:
single button which creates a frmDialog2 and calls ShowDialog on it.
frmDialog2:
does nothing (ie. blank)
when they were all running I could access/drag mainform. I could also do the same with frmDialog1 (both versions) only if I hadn't clicked the button that shows dialog 2.