Monthly Archives: April 2017

Display context menus for TreeView items in C#

Posted on April 28, 2017 by Rod Stephens

This example displays different context menus when you right-click on different kinds of nodes in a TreeView control. In this example, different nodes represent factories, groups, or individuals. Different node types display different context menus. When it starts, the program … Continue reading →

Posted in controls, user interface | Tagged , , , , , , , , , , | Leave a comment

Enumerate TreeView nodes in C#

Posted on April 27, 2017 by RodStephens

The previous two posts show two ways you can enumerate TreeView nodes that are checked. The idea is to recursively crawl over the tree’s nodes and pick out the checked ones. Unfortunately that method isn’t easily extendable. For example, if … Continue reading →

Posted in algorithms, controls, recursion, user interface | Tagged , , , , , , , , , , , , , , , , | Leave a comment

Yield checked TreeView nodes in C#

Posted on April 26, 2017 by RodStephens

The previous example used recursion to traverse the nodes in a TreeView control and fill a list with the nodes that are checked. This example uses a slightly different approach. It traverses the TreeView control’s nodes and uses the yield … Continue reading →

Posted in algorithms, controls, recursion, user interface | Tagged , , , , , , , , , , , , , , | Leave a comment

Make a list of checked TreeView nodes in C#

Posted on April 25, 2017 by RodStephens

If you set a TreeView control’s CheckBoxes property to true, then the control displays boxes that the user can check to select nodes. In that case you will probably need to find the checked TreeView nodes at some point. Strangely … Continue reading →

Posted in algorithms, controls, recursion, user interface | Tagged , , , , , , , , , , , , , | Leave a comment

Display tooltips for TreeView nodes in C#

Posted on April 24, 2017 by Rod Stephens

At design time, I added a TreeView control to the form. I also added an associated ImageList control to hold images for the TreeView control’s nodes, and I set the TreeView control’s ImageList property to the ImageList control. Finally I … Continue reading →

Posted in controls, user interface | Tagged , , , , , , , , , , , , , | 1 Comment

Compare sorting algorithms in C#, article 5 of 5

Posted on April 21, 2017 by Rod Stephens

Countingsort The discussion of Quicksort in my previous post mentions that the fastest possible sorting algorithms that use comparisons take on the order of N * log(N) steps. Countingsort does not use comparisons so it is not bound by that … Continue reading →

Posted in algorithms, performance | Tagged , , , , , , , , , , , , , , | 1 Comment

Compare sorting algorithms in C#, part 4 of 5

Posted on April 21, 2017 by Rod Stephens

Quicksort Quicksort is a recursive algorithm that uses a divide-and-conquer technique. While the list of items to be sorted contains at least two items, Quicksort divides it into two sublists and recursively calls itself to sort the sublists. The Quicksort … Continue reading →

Posted in algorithms, performance | Tagged , , , , , , , , , , , , , | Leave a comment

Compare sorting algorithms in C#, part 3 of 5

Posted on April 20, 2017 by Rod Stephens

Selectionsort Selectionsort is a very simple algorithm. First you search the list for the smallest item. Then you swap that item with the item at the top of the list. Next you find the second smallest item and swap it … Continue reading →

Posted in algorithms, performance | Tagged , , , , , , , , , , , , , , | Leave a comment

Compare sorting algorithms in C#, part 2 of 5

Posted on April 19, 2017 by Rod Stephens

Bubblesort Bubblesort is a specialized algorithm designed for sorting items that are already mostly in sorted order. If only one or two items in your list are out of order, Bubblesort is very fast. If the items in your list … Continue reading →

Posted in algorithms, performance | Tagged , , , , , , , , , , , , , , | Leave a comment

Compare sorting algorithms in C#, post 1 of 5

Posted on April 18, 2017 by Rod Stephens

This post begins a series of articles about sorting algorithms. Much of the text originally appeared in the December 1995 issue of Visual Basic Developer magazine, a publication that seems to no longer exist. All of these posts include the … Continue reading →

Posted in algorithms, performance | Tagged , , , , , , , , , , , , , , | 6 Comments