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ASP.NET TreeView Sort

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11 Sep 2011CPOL 47.6K   3   8
Easy way to sort nodes in a TreeView using a recursive function.
A few days ago, I needed to sort the nodes of a tree view. The solutions that I found over the Internet did not please me, so I decided to write my own. This solution is a simple recursive function that sorts tree nodes in an alphabetic order.

Create your tree view and add your nodes:


C#
TreeView mytree = new TreeView();
//add your nodes here

Then simply call the sort function with the main node as the argument:


C#
sort(node);

Here is the recursive function:


C#
private void sort(TreeNode node)
{
    foreach (TreeNode n in node.ChildNodes)
        sort(n);
    try
    {
        TreeNode temp = null;
        List<TreeNode> childs = new List<TreeNode>();
        while(node.ChildNodes.Count>0)
        {
            foreach (TreeNode n in node.ChildNodes)
                if (temp == null || n.Text[0] < temp.Text[0])
                    temp = n;
            node.ChildNodes.Remove(temp);
            childs.Add(temp);
            temp = null;
        }
        node.ChildNodes.Clear();
        foreach (TreeNode a in childs)
            node.ChildNodes.Add(a);
    }
    catch { }
}

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Software Developer (Senior) Martifer Inovação e Gestão
Portugal Portugal
This member has not yet provided a Biography. Assume it's interesting and varied, and probably something to do with programming.

Comments and Discussions

 
Questionincorrect comparison Pin
Member 1024692319-Nov-14 3:04
Member 1024692319-Nov-14 3:04 
Suggestioncompare full words Pin
Klimovec12-Apr-12 2:49
Klimovec12-Apr-12 2:49 
GeneralHeyy it worked for me. Currently i have a treeview which pop... Pin
rjkumar19879-Jan-12 2:27
rjkumar19879-Jan-12 2:27 
GeneralRe: just replace the logical comparison "n.Text[0] < temp.Text[0... Pin
brunofer200714-Jan-12 23:59
brunofer200714-Jan-12 23:59 
General1-The datasource should be sort not the tree in asp.net. An... Pin
JoePatent13-Sep-11 8:03
JoePatent13-Sep-11 8:03 
1-The datasource should be sort not the tree in asp.net. And then you fill the tree...
2- recursive function should always be avoid in prod development. This could be the source of instability. You can't predict the number of iteration and consequently the resources that will be required to run your routine.
3- foreach (TreeNode n in node.ChildNodes)
if (temp == null || n.Text[0] < temp.Text[0])
temp = n;
This need explanation. As soon as your temp is null you should not even execute your for each loop. That's a waste of time.
4-Also, there is already existing sort algorithm to accomplish this without having to code yourself an average one like this one based on bubble sort algo.
GeneralRe: 1 - Sometimes a TreeView doesn't have necessarily a datasour... Pin
brunofer200714-Sep-11 0:36
brunofer200714-Sep-11 0:36 
GeneralCould I ask, why can't you use the default TreeView Sort met... Pin
George Swan11-Sep-11 20:11
mveGeorge Swan11-Sep-11 20:11 
GeneralRe: Hello George, as you can see in the title, this solution is ... Pin
brunofer200711-Sep-11 22:21
brunofer200711-Sep-11 22:21 

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