Tree view in combobox in C#

Question

Hi all,
I want to show a drop down list (combo box) with a tree view in c# application. I want to drop down the tree when i click on the combo box.
If anybody have a solution then it will be helpful...
thanks in advance

Habibul Rehman · Answer

https://blogs.msdn.microsoft.com/jfoscoding/2005/03/03/getting-combobox-to-show-a-treeview-whidbey/ Please visit given link you will find very helpful this article with code

felonious monk · Answer

it really makes perfect sense. Not sure what you mean about limiting the functionality of the treeview ... the purpose is to have a treeview control in the same space that you would have a dropdown. think of it differently still: suppose i have 400 items to put in a dropdown .. but those 400 items could be broken in sub-categories to make it more user-friendly. so now you could still keep the flat (aka, not collapsible) metaphor, but simply add a left-margin bump for each category level. Still, the user has to scroll through a list 400 long. Well, now we're in the territory of needing a treeview to do expansion/collapsing, and now you should clearly see why this is a common need... sure, for a finite number of depths, you could simply have that many dropdowns on your control. but if real estate is a commodity, you don't want to clutter it up with something when you could just use a tree to represent the data. A better way to think about what functionality is broken, is that of the dropdown with respect to clicking == selection == dropdown closing. It's really a quite simple case, however -- if the treeview selecteditem doesn't change, then the dropdown shouldn't close. you could also implement double-clicking == close, but I don't like adding double-click requirements to selection ..

theLizard · Answer

Venkatesh the solution is very simple, you create a new control with all the properties and events you want to handle like I said in my first reply to this post you use a TextBox, a Button and a TreeView on a Panel then add all the additional properties and events you want to handle. Why would you want a drop down tree view, does anyone have an answer for me? I have created a number of custom controls in C# and C++ and have never had a reason to create a DropDown TreeView control it makes no sense because a tree view is designed to show an hierarchical representation of relevant information, putting this in a drop down hides the versatility of a TreeView control.

Venkatesh Ellur · Answer

Hi if you are looking for displaying the tree view control in a dropdown list box that would be possible in windows forms. As per one of the responses there is a sample code in codeproject.com but when it comes to web application I dont think that would be possible because we have controls as container controls and data controls in asp.net both dropdown list box and treeview controls are data controls. how ever please let me know if you get any solution for this issue.

theLizard · Answer

Yes, it is what I said in my first post, all it is is a text box button and a tree view and you could easily create the illusion of a drop down combo box with tree view without actually creating a custom control, the example on codeproject would, I imagine, have a number of problems to deal with, the nature of drop downs is that when you select an item, the drop down rolls up and disappears, for a treeview, this would be a real problem because you would want to click on a node and expand it's children. My question still stands, why would you want a tree view in a drop down in the first place. Give me an example of why it could be beneficial. I have a TreeView where you can assign an object of DropDownComboBox, a GridView, A ListView and a custom combopanel with a close button to tree nodes.

Master Billa · Answer

Hi We can do here is control http://www.codeproject.com/KB/tree/dropdowntree.aspx thank you

Master Billa · Answer

Hi I think you have some problems. Please check again that link , they have put image also http://www.codeproject.com/KB/tree/DropDownTreeView.aspx?msg=1689247 thank you

theLizard · Answer

Master Billa , the link you posted to the example code is for a ComboBox in a Tree View NOT a Tree View in a Combo Box. So I ask the question why would you want a TreeView IN a ComboBox for, it makes little sense to do that. see my lizardControls for WinForms at http://c-sharplizards.com/lizardControls.aspx

Master Billa · Answer

Hi It's easy work here is code to do this http://www.codeproject.com/KB/tree/DropDownTreeView.aspx?msg=1689247 thank you

jinge · Answer

The link I provided to you does not work? -

theLizard · Answer

Depends on how much work you want to do to get what you want. One way is to create your own user control with a standard text box, an image button and a tree view control, when the button (drop down arrow) is pressed the TreeView becomes visible and while it has mouse capture it stays visible, when mouse leaves it hides itself. There is a bit of work involved but you can do it... I am curious, why would you want a drop down list with a TreeView in its drop down. I can't imagine a reason why you would want this type of control.

Jisss shyam · Answer

thanks for your reply kirtan Actually i want this in c# windows application, not web application. Any other solution for this? thanks

jinge · Answer

You can find the code here: http://blogs.msdn.com/jfoscoding/archive/2005/03/03/384430.aspx

Kirtan Patel · Answer

Better to USe Telerik Control in this case they are not free but they are Very Good in UI look and Stability http://demos.telerik.com/aspnet-ajax/treeview/examples/functionality/treeviewcombobox/defaultcs.aspx

Tree view in combobox in C#

Answers (14)