Multi-level treeView from a dataset

Question

Hello I am building a Windows Forms application with C#. I have created a table with these columns: (FolderID FolderName ParentFolder) This is an example of how records have been stored: ================================ FolderID FolderName ParentFolder ================================ 1 Folder1 2 Folder2 3 Folder3 1 4 Folder4 1 5 Folder5 2 And this is how I need to view the tree: -Folder1 --Folder3 --Folder4 -Folder2 --Folder5 How can I add data to the treeView as shown above given that database records are already in a datable. Thank you in advance.

Jaganathan Bantheswaran · Answer

Hi http://www.c-sharpcorner.com/UploadFile/c5c6e2/populate-a-treeview-dynamically/ http://social.msdn.microsoft.com/Forums/windows/en-US/693b8f6d-54e4-436d-9363-e39047b08208/fill-tree-view-dynamically-from-sql-database-using-c?forum=winforms T ake a look there. It may help you.

Dealy · Answer

I just fixed the problem I had an issue with my database records. Thank you for all the help.

sourav mondal 0 · Answer

HERE IS COMPLETE SOLUTION + STEP BY STEP TUTORIAL + SOURCE CODE + VIDEO TUTORIAL http://dotnetawesome.blogspot.com/2013/11/how-to-bind-treeview-from-database.html

Dealy · Answer

http://www.c-sharpcorner.com/UploadFile/c5c6e2/populate-a-treeview-dynamically/ That's what I needed thanks a lot! :) I have a problem with populateTree though it gets into infinite loop even though i followed the above example. private void PopulateTreeView(SqlConnection connint parentId TreeNode parentNode TreeView treeView) { SqlCommand cmd = new SqlCommand(SELECT_SUBFOLDERS conn); cmd.CommandType = CommandType.StoredProcedure; MessageBox.Show(Parent: +parentId); cmd.Parameters.Add(new SqlParameter(@FolderId parentId)); SqlDataAdapter da = new SqlDataAdapter(cmd); DataTable dtChild = new DataTable(); da.Fill(dtChild); TreeNode childNode; foreach (DataRow dr in dtChild.Rows) { if (parentNode == null) childNode = treeView.Nodes.Add(dr[SubfolderDescr].ToString()); else childNode = parentNode.Nodes.Add(dr[SubfolderDescr].ToString()); PopulateTreeView(conn Convert.ToInt32(dr[SubfolderID].ToString()) childNode treeView); } } //End of PopulateTreeView Any suggestions? Thank you.

Dealy · Answer

First of all thank you for the answer. I'm not sure I understood your suggestion. I have already retrieve the data from SQL Server into a dataset in the form of (FolderID FoldernameParentID). What I need is to populate the tree from the dataset based on ParentFolder. Thanks again.

Jaganathan Bantheswaran · Answer

Hi First you create a class called something like TreeNode. In this class include properties such as: public TreeNode Parent IList Children Then Use linq to get the right data with grouped by ParentFolderId & create the treeview using the collection returned by the linq.