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.NET C# Using TreeView in WinForms like tab control

I want to use TreeView in my software so when user clicks a node, the content of the Form will be changed. Example in this picture, but also I want to grab user input from all forms.
WinForms TreeView example
https://youtu.be/9BdYzMDxl9M?t=46
TreeView -> Node -> User Click -> Display Form_X in the GroupBox
I tried but I could not find related resources on this topic so I posted this question. Thank you for your help

Don't use forms as child controls. User controls exist specifically for that so use them. You add a user control to a project in the same way as you do a form, simply selecting a different menu option. You then design it and add code to it just as you would a form. Once you build your project, the user control will appear in the Toolbox and you can use it just like you would any other control. You then have a couple of options for how to handle switching controls via the TreeView.
If the number of controls is fairly small, you can add one of each to the GroupBox in the designer, so they all exist all the time. You would probably want to set the Dock property of each to Fill, so they all fill the parent GroupBox. In the Load event handler of the form, you can assign each user control instance to the Tag property of the corresponding TreeNode. When the user selects a node, you get the user control from its Tag property and call BringToFront on it, so the user will see it and it will hide all the other user controls, e.g.
private void Form1_Load(object sender, EventArgs e)
{
var nodes = treeView1.Nodes;
nodes[0].Tag = userControl1;
nodes[1].Tag = userControl2;
nodes[2].Tag = userControl3;
}
private void treeView1_AfterSelect(object sender, TreeViewEventArgs e)
{
var userControl = treeView1.SelectedNode.Tag as Control;
userControl?.BringToFront();
}
Because all the controls exist all the time, you can load all the data at the start and save all the changes at the end and not have to transfer any data when the selection changes.
If the number of controls is larger, you might want to show just one at a time. That becomes more complex because, when the selection changes, you have to make sure that any changes in the current user control are remembered, remove the existing control and then create and load the new control. Because the process is more complex, there are more options about exactly how to implement it. For that reason, I won't go into specifics here. If you want to go that way, you need to consider those options and how they relate to the specifics of your application and then decide how you want to implement the process. If you do that and encounter an issue along the way, that would be another question.

What have you tried? I am confident there are many ways to achieve what you describe. Since you mentioned a TabControl have you considered using a TabControl without the Tabs and manually switch to the proper tab page whenever the tree view node is clicked.
Something like…
private void Form1_Load(object sender, EventArgs e) {
tabControl1.Appearance = TabAppearance.FlatButtons;
tabControl1.ItemSize = new Size(0, 1);
tabControl1.SizeMode = TabSizeMode.Fixed;
}
private void treeView1_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e) {
if (e.Node.Name == "TabPage1") {
tabControl1.SelectTab("TabPage1");
}
else {
tabControl1.SelectTab("TabPage2");
}
}

Devexpress.XtraTreeList click node

I have a Devexpress.XtraTreeList component. I want to catch in click event where the user is clicked on expand button or the node? How can I understand this?
Edit: Actually I am trying to do something like outlook using treelist. When I click the node, for example inbox, the messages in inbox are shown right side on the screen. When the user click another node, the treelist must be updated because some messages may be read. I did this functions in click event. It ıs OK. But in this case expand buttons functionality does not working normally.

I found the solution..
Thanks everyone..
private void treeList1_Click(object sender, System.EventArgs e) {
DevExpress.XtraTreeList.TreeList tree = sender as DevExpress.XtraTreeList.TreeList;
DevExpress.XtraTreeList.TreeListHitInfo info = tree.CalcHitInfo(tree.PointToClient(MousePosition));
if(info.HitInfoType == DevExpress.XtraTreeList.HitInfoType.Cell)
... // your code is here
}

There is no event that fires when a Node is clicked. However, here are some other events that might interest you:
AfterExpand - Fires immediately after a Node has been expanded.
BeforeExpand - Fires before a Node is expanded.
FocusedNodeChanged - Fires immediately after changing the focused Node (which happens when the user selects a Node, regardless of whether they clicked on it or used an arrow key to get there).
I'll also note that DevExpress has their own knowledge base with examples and sample code. It would be a great place to start your research for future questions: http://www.devexpress.com/Support/Center/

private void xtraTree_AfterFocusNode(object sender, NodeEventArgs e)
{
}
You can handle the above event on the XtraTreeList control and then extract the Node that was clicked on from the NodeEventArgs - e.Node

C# WinForms Right Click Context Menu without Selecting item

I have a right click menu on c# winforms and the question is when I right click to get the menu how do I not get it to select the item when I right click?
I found a similar question, but it is for WPF here at this link
The problem being that i have index_changed event that is affected by the right click and i don't want it to be.

I am guessing that you want this to be handled in the Listviews selected index changed event..... The sample below shows how to determine the button pressed. Al it does is tell you yes or no if the right mouse button was clicked. This is the simplest example I can show without knowing your code.
private void listView1_SelectedIndexChanged(object sender, EventArgs e)
{
MessageBox.Show(Form.MouseButtons.HasFlag(MouseButtons.Right).ToString());
}

Detect if mouse click hits a item not in listbox [C#]

If the user click on a item in the listbox, the listboxItems_SelectedIndexChanged is called. But, even if the user miss an item and randomly clicks inside the listbox (not on items) the listboxItems_SelectedIndexChanged is still called.
How can I change this? I only want action on item click.
Note: removing the ability to navigate the application with keyboard is not a option.

I guess that in some cases you don't have enough list items in your control, therefore you have some space that you can click on and then SelectedIndexChanged is fired.
I guess you cannot dynamically resize the control to always fit the number of list items or else you wouldn't be asking this question.
Now, what should happen when the user click (selects) the same list item? Should some logic happen even though the selected index is the same (so when it was clicked the first time the same logic happend)?
If you require that selecting the same index more than once should be ignored then you could use the following hack:
Keep a variable at the form scope (the form containing the listbox control) and each time the selection index changes set that variable. Then use it later to check if the same selection has been made to ignore handling the event. Here is an example:
private int _currSelIdx = -1; // Default value for the selected index when no selection
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
if (listBox1.SelectedIndex == _currSelIdx)
return;
Console.WriteLine(listBox1.SelectedIndex);
_currSelIdx = listBox1.SelectedIndex;
}
It ain't pretty, but hey...whatever works!

Maybe SelectedIndexChanged is not the right place to put your logic, since it is triggered even when you change the selection with the keyboard.
I would use MouseClick instead, checking if the click occurred over the selected item, i.e. something like this:
private void listBox1_MouseClick(object sender, MouseEventArgs e)
{
if (listBox1.SelectedIndex < 0 || !listBox1.GetItemRectangle(listBox1.SelectedIndex).Contains(e.Location))
MessageBox.Show("no click");
else
MessageBox.Show("click on item " + listBox1.SelectedIndex.ToString());
}

This link may help, instead of double click, implement the same for single click
i want to detect an item double click in a winforms listbox control. [how to handle click on blank area?]

Focusing WebBrowser control in a C# application

I have a WebBrowser control hosted in a windows Form. The control is used to display hyperlinks which get created at runtime. These links point to some HTML pages and PDF documents.
The problem is that when the form hosting the browser control is loaded, the focus is on the form. When the TAB key is pressed, the focus does not shift to the first hyperlink. However, if I perform a mouse click on the control and then hit the TAB key, the tab focus is now on the first hyper link. I tried using Select() on the WebBrowser control and then I called Focus(), but it doesn't solve the problem.
Any ideas on how to set the tab focus on the first hyperlink at load? Thanks.
Cheers,
Harish

I guess it might be because the focus is set before the page is fully loaded. Try this:
private void Go(string url)
{
webBrowser1.Navigate(url);
webBrowser1.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(webBrowser1_DocumentCompleted);
}
void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
webBrowser1.Document.Body.Focus();
}
You could also automatically select the focus on the first link directly by getting the HtmlElement of that first link.
If the above doesn't work, you might want to check other parts of your code to see if anything else is capturing the focus. Try searching for Select, Focus and ActiveControl in your code.

Use form.ShowDialog(form) instead on form.Show(), then it will work !
where form is the running instance of your windows Form

This is my solution
private void txtAdres_KeyPress(object sender, KeyPressEventArgs e)
{
int licznik = 1;
if (e.KeyChar == (char)13)
{
string adres = txtAdres.Text;
webBrowser1.Navigate(adres);
licznik = 0;
}
if (licznik == 0)
{
webBrowser1.Focus();
}
}

In a normal scenario it should be sufficient for you to set the TabIndex of the WebBrowser control to zero. This way, when the form loads the control will be focused and pressing TAB will iterate through the links.
Note that you should also change the TabIndex of the other controls on the form.
If this does not solve your problem, you need to add more detail on the complexity of the form hosting the control.