37 Reusable Code Snippet Topics
Remove Filter  | I wrote a timer/alarm app in Python that I wanted to be accessible from all Windows Desktops. What I had to do until recently was run the app, select the desktops icon on my toolbar, then right click the app and select "Show this window on all desktops". I was …  |
| | Sometimes you want to ensure that only one copy of a script can be run at time. Windows provides a facility called a mutex and you can use it to prevent multiple instances. To create the mutex, all I have to do is varname = GetMutex() If the mutex already … |
| | ##This project implements a multiple timer application. It was written in 1. Python 3.8.2 2. wxPython 4.1.0 Feel free to experiment. Here are some possible enhancements: 1. Add the ability to run a program when the timer expires. With a little scripting you could, for example, schedule the sending of … |
| | I have a Chromecast that I use to stream video from my laptop to our TV. It works great, however, until VLC (Videolan) releases their promised upgrade with Chromecase support, I am limited to streaming files in the mp4 format. Fortunately, ffmpeg allows me to convert other formats to mp4. …  |
| | A long standing complaint with the standard progress bar control is that there is no easy way to display text. In spite of numerous requests, Microsoft has not included this capability. The following code includes a class, `CustomProgress` which inherits the standard `ProgressBar` and adds such a feature. It is … |
| | As part of a project to manage my collection of photos, I wanted to add the capability of displaying a series of files as thumbnails. This posed me with three problems: 1. how to preserve the aspect ratio of the original images 1. how to generate the thumbnails without tying … |
| | vbScript - Extending Application Functionality with vbScript and AutoIt Sometimes you'll find that one of your favourite applications is missing some useful functionality. For me, it was FastStone Image Viewer. I've had to scan a large number of family photos to convert everything to digital. Rather than scan one photo … |
| | vb.Net - Regular Expression Tester Every now and then I find another use for a regular expression. For those not familiar with regular expressions, they can be as cryptic to read as strings of Greek letters. Simply put, regular expressions are just patterns. If you've ever used the DOS command … |
| | vbScript - Create a Log File Using vbScript Classes Before I retired I was responsible for most of the corporate data plumbing at our control centre. All of the plumbing was written in vbScript. As any maintenance programmer knows, log files are a vital key in identifying and fixing problems. … |
| | ##vbScript - Run an External Program and Capture the Output Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. When you want to execute an external program for a particular result (such as resizing an image, as shown in a previous snippet) you can simply use … |
| | Over the last few days I have been converting old video files from avi to mp4. I've been doing this using the command line version of DivX. This is the process behing the DivXPro GUI and it is named `DivXEngine.exe`. Converting video files takes a big hit on the CPU … |
| | ##vbScript - An Application to Modify srt Subtitle Files Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. So far I've posted either functions/subs or code snippets to illustrate a technique. This time I am going to post a complete application. First, a few points. 1. … |
| | ##vbScript - A Multi-column Sort With Minimal Coding Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. A previous post dealt with sorting. The code easily handles sorting simple things like lists of words, lines of text - cases where you only had to compare two … |
| | ##vbScript - Some Useful String Functions Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. vbScript provides a number of functions for manipulating strings. I find that a few more simple functions would have made things a lot simpler. For example, I find myself checking to …  |
| | ##vbScript - Identify File by Perceived Type Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. There are times when you want to operate on all files of a given type. For example, you may want to enumerate all files in a folder or a drive … |
| | ##vbScript - Get Drive Letter by Volume Label Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. I have all my computers partitioned with two partitions. The drive letters are C (OS and applications) and D (user data). I use Macrium Reflect to take monthly full … |
| | ##vbScript - Browse for Folder or File Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. Some scripts need input (other than from the command line) from the user. This can be read from the console (StdIn) or from a pop-up textbox (InputBox). This is fine … |
| | ##vbScript - Convert Integer to Binary String Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. vbScript has a number of functions for converting from one type to another. These functions are named C<type> as in CInt (convert to int), CDbl (convert to double), etc. There … |
| | ##vbScript - Sorting With and Without Code Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. Sorting is something that must be done from time to time. I'm going to examine three ways. The first is the well known (at least by name) QuickSort method. Rather … |
| | This is the first in (hopefully) a series of posts about vbScript. Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. My wife and I take a lot of pictures. Naturally, we end up sending pictures to friends through email. I find it is unnecessary, and … |
| | This code generates an ascii maze of up to size 30x30. If you try to generate a larger maze then you will likely run out of stack space. There is no way to increase the size of the stack in vbscript. Each cell in the maze is represented by a … |
| | Over the years I've seen a lot of discussion (and several implementations) of the Quicksort algorithm. Most of what I have seen, unfortunately, lacks sufficient commenting as well as meaningful variable names. Hopefully the following vbScript code will more clearly show how Quicksort actually works. A couple of incidental notes: … |
| | An often underused control from vb.Net is the FolderWatch control. But sometimes you need to throw something together that doesn't need a fancy GUI. Or perhaps the task seems too trivial to go to the hassle of coding it up in vb.Net (or C#). Because the FolderWatcher is built on … |
| | Several people have asked how to export data to Excel. This code snippet shows how to export the data from a listview in details mode to a new Excel spreadsheet. Take note of the comments in the header to avoid having orphaned Excel.exe tasks eat up your system memory. |
| | A while back I came across an article that mentioned genetic algorithms. For those unfamiliar with the term, simply put, rather than finding a solution to a problem by iterating over all possible cases, a genetic algorithm attempts to find a solution by starting with a guess, then generating a …  |
| | Here's an interesting little scenario. You get challenged to a game of coin toss. Both players pick a sequence of coin toss results (heads or tails). The coin is repeatedly tossed until the sequence for one of the players occurs. The loser pays the winner a dollar. You'd assume that …  |
| | Sometimes you want to add a little functionality to an existing class but you don't want to go to the trouble of sub-classing. A technique that you can use is known as **Extending**. For example, I frequently use regular expressions when working with strings. Wouldn't it be nice if strings …  |
| | If your Excel spreadsheet is laid out as regular columns and rows with a header row that identifies the columns then this code will allow you to read the data using ADODB the same way you would read records from a database table. To try this code 1. Create a … |
| | Several people have asked about storing binary data in a database. I coded up an example today that uses an ADODB.Stream to copy the binary data but after some fiddling I found a more direct way. If you are using MS SQL Server, the easiest way I have found is … |
| | I find that I occasionaally have special projects where it would be nice to have a context menu for files. I tend to write housekeeping scripts and it is convenient to be able to run these scripts against one or more files at a time without having to navigate and … |
| | A lot of questions in the VB.NET forum are database related. Most of the code that gets posted result in one or more comments like "use parameterized queries to avoid SQL injection attacks". I won't describe the nature of a SQL injection because it is easily looked up via google. … |
| | One of the things I have been steadfastly avoiding is writing code to print stuff. Most of what I want to print is from withing apps like Outlook or Word that already provide that functionality. But I finally ended up having to bite the bullet. What I ended up with …  |
| | The code in this snippet (and attached project zip) demonstrates how to use a background worker thread to monitor a network address (name or IP). It shows how to start and stop the thread and how to update controls in the main thread using delegates. It should be simple to … |
| | This is a short bit of code that shows how to implement sorting on columns in a details-mode ListView. Suggestions for improvement are always welcome. One possible improvement would be to modify the column headers to indicate which column is being sorted and in which direction. |
| | Sometimes sorting data can be easy and sometimes it can be difficult. If you have data in a listview you can spend a great deal of time writing ICompare functions. This is appropriate for non-trivial applications but can be a little intimidating for inexperienced programmers. Also, it is a problem … |
| | This code demonstrates how to add controls to a form at run time. The number of rows and columns, the spacing between the controls and the size of the controls are all determined by Consts, but this could easily be changed so that the parameters are user entered. My example … |
| | I wrote this 3D Breakout game as a sample project to learn both Python and the visual module, vPython. It is based on a similar game I had on my Amiga back in the 80s. I don't expect that my Python is either standard or as elegant as it could … |
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