Latest News from RickStrahl
A news aggregator from various RSS feeds, like technology, gaming, development and general news sites.
Resolving Paths To Server Relative Paths in .NET Code
ASP.NET Core automatically resolves 'virtual' paths in Razor pages or views to a site relative path.Note that more than likely you'd want to pass in all the parameters for base path, current page and host information, if you're processing the Url generically.In this post I've described a couple of helpers that do exactly that and even if you don't use these as is, they should give you the basis for resolving Urls in any Web scenario...
Inline Confirmations in JavaScript UI
What if you could instead use an inline UI to confirm an operation?In this post I describe a simple way you can use an inline UI to confirm an operation that can be easily implemented with a few lines of code and a couple of binding directives.I recently ran into an app that was using a nice and simple UI to handle confirmation of deletions by using a dual interface for the confirmation prompt - a button - to both start and confirm a delete operation.
Retrieving Images from the Clipboard Reliably in WPF Revisited
Recently however I started noticing some issues with some of my clipboard pasting code in Markdown Monster producing what appears to be corrupted images when displaying in an ImageSource control.What's happening in this code is that the image is copied to the clipboard from SnagIt and then picked up by the form when it loads from the clipboard and loaded into an Image control via an ImageSource bitmap.WPF Image Clipboard operations have been notoriously difficult to work with, but with this circuitous workaround described in this post, that first loads a bitmap and then an ImageSource from that, it's possible to load the vast majority of images reliably.
Comparing Raw ASP.NET Request Throughput across Versions: 8.0 to 9.0 Edition
Whenever a new release of .NET comes out I run a comparison test of versions using some of my own load testing tools and in this post I look at .NET 8.0 to 9.0.WebSurge can also run non-UI tests from the command line and these tests tend to be a bit more efficient as they don't have to deal with the overhead of even minimal UI updates.NET's performance trajectory has been on a steep upward trend and in this release that trajectory has leveled out a bit.
Back to Basics: Using the Parallel Library to Massively Boost Loop Performance
A few days ago I posted a quick note on X about a specific use case of using the Parallel library in .NET to massively optimize a link look up operation in Markdown Monster with very little code.The specific scenario I'm going to talk about is a Markdown link checker in my Markdown Monster editor that collects all links in a Markdown document and then checks those links - both local and online - for validity.However, after updating to using parallel code checking all links is drastically faster taking roughly the amount of time of the slowest link to process.
Getting the Current TabItem when the Tab is not selected in WPF
The icon tabs on the left can be accessed with the context menu even when the tab is not active.The key here is a small utility function WindowUtilities.FindAncestor<T>() which is used to walk up the control hierarchy to see if there's a matching control of the provided generic type - in this case a MetroTabItem (a TabItem subclass from MahApps.Metro)./// Finds a type of element in the parent chain of an element
Using Sql Server on Windows ARM
I recently picked up a Windows ARM device in the form of a Samsung Galaxy Book 4 with a SnapDragon X Elite chip.And yes, this is the SQL Server Express installer, but that installer also includes the LocalDb installer and so you go through most of the SQL Express setup - but without actually installing Express.If you want to do connect to the database in code you can do that with a connection string that looks like this:
Getting the ASP.NET Core Server Hosting Urls at Startup and in Requests
So the task at hand is to get the Hosting Urls as part of the startup code in program.cs so that it can be written out as part of a start up banner as shown in Figure 1.Effectively you have to put the Url retrieval code towards the very end of your startup code after the server has been started.You can also retrieve the host urls inside of a request by requesting a IServerAddressesFeature from an IServer instance and then requesting the feature and the addresses:
Getting the ASP.NET Core Server Hosting Urls at Startup and in Requests
Today I was helping out a customer with their ASP.NET core application that wasn't starting up on a live server, hosted in IIS.So the task at hand is to get the Hosting Urls as part of the startup code in program.cs so that it can be written out as part of a start up banner as shown in Figure 1.You can also retrieve the host urls inside of a request by requesting a IServerAddressesFeature from an IServer instance and then requesting the feature and the addresses:
Nuking Local Nuget Package Sources to show newly Published Packages
The command to clear the caches is a NuGet command that also works through dotnet nuget, but it's not widely advertised and not easy to find unless you know what you're looking for in the first place.The command to force the NuGet package sources to reload is:But there's a drastic solution available in the .NET NuGet local all command, at least, if you have the bandwidth and speed to deal with the fallout of having to re-download all your packages.
Nuking Local Nuget Package Sources to show newly Published Packages
The command to clear the caches is a NuGet command that also works through dotnet nuget, but it's not widely advertised and not easy to find unless you know what you're looking for in the first place.The command to force the NuGet package sources to reload is:But there's a drastic solution available in the dotnet nuget local all --clear command at least, if you have the bandwidth and speed to deal with the fallout of having to re-download all your packages.
Create a .NET PlantUML Markdown Render Extension
In the process I'll highlight a useful library and service that is PlantUML, and how you can add support for it in your own C# code, or use a custom RenderExtension in Markdown Monster or elsewhere to pre-process Markdown for PlantUML diagrams.Once you've created the addin you can create a new RenderExtension class in the project:Next you need to hook the actual pre and post processing into your Markdown parsing pipeline.
Create a .NET PlantUML Markdown Render Extension
In the process I'll highlight a useful library and service that is PlantUML, and how you can add support for it in your own C# code, or use a custom RenderExtension in Markdown Monster or elsewhere to pre-process Markdown for PlantUML diagrams.Once you've created the addin you can create a new RenderExtension class in the project:Next you need to hook the actual pre and post processing into your Markdown parsing pipeline.
Back to Basics: Await a Task with a Timeout
Task natively doesn't have a way to provide for a timeout on a single task, and by default an await call on a task results in an indefinite wait on the task to complete which...If you prefer to retrieve the result, but deal with exceptions instead, you can use the TimeoutWithResult() method instead, which directly returns a result and throws an exception if the operation times out.I also added these functions into Westwind.Utilities in the AsyncUtils class as extension methods to Task.
Work around the WebView2 NavigateToString() 2mb Size Limit
The WebView2 control's NavigateToString() method has a limit for the string size of 2mb, which can be a problem especially for HTML pages with embedded content. In this post I'll describe how this problem can show up and show a couple of ways to work around the issue.
Work around the WebView2 NavigateToString() 2mb Size Limit
The WebView2 control's NavigateToString() method has a limit for the string size of 2mb, which can be a problem especially for HTML pages with embedded content. In this post I'll describe how this problem can show up and show a couple of ways to work around the issue.
Dealing with Platform Specific Classes and Methods in CrossPlatform .NET
If you deal with old .NET library code that is sprinkled with some Windows specific code in places you've likely run into places where the Windows specific code is throwing up unwanted compiler warnings. Sometimes that matters, but often times these warnings are annoyances as these methods are highly unlikely to get called from x-platform code. In this post I describe some annoyances, how you can work around them and eventually fix the issues without throwing everything out the window.
C# Version String Formatting
I'm tired of trying to format versions for user facing interfaces after fumbling with it again and again. In this short post I show a small helper extension method that lets you configure how to form user friendly version strings to display to end users.
C# Version String Formatting
I'm tired of trying to format versions for user facing interfaces after fumbling with it again and again. In this short post I show a small helper extension method that lets you configure how to form user friendly version strings to display to end users.
Mime Base64 is a Thing?
Ran into an old legacy application recently that required that attached data was preformatted to Mime Base64 which I never even heard of before. Turns out it's a 'url-safe' version of base64 that replaces certain characters that can be present in base64 with 'safe' characters. In this short post I show a small helper that handles several Base64 Mime operations.
Speed up your Start Menu by disabling Web Search
If you're like me, you've probably cursed the Windows Start menu from time to time, when it's either very slow to pop up, or in some instances fails to pop up at all when you press the Windows key. This simple tip can drastically improve performance of your Windows Start Menu by simply disabling Web search.
ASP.NET Core Hosting Module with Shadow Copy Not Starting: Separate your Shadow Copy Folders!
I recently ran into a major failure related to Shadow Copying for an ASP.NET Web app on IIS which was caused by corruption of the Shadow Copy directories. The app starts with the dreaded white ANCM Error page and event log entries that point at missing application folders. It turns out that this is caused by interference of multiple applications using the same shadow copy folder. In this post I describe the problem and how to work around it.
ASP.NET Core Hosting Module with Shadow Copy Not Starting: Separate your Shadow Copy Folders!
I recently ran into a major failure related to Shadow Copying for an ASP.NET Web app on IIS which was caused by corruption of the Shadow Copy directories. The app starts with the dreaded white ANCM Error page and event log entries that point at missing application folders. It turns out that this is caused by interference of multiple applications using the same shadow copy folder. In this post I describe the problem and how to work around it.
Programmatic Html to PDF Generation using the WebView2 Control with .NET
In this post I describe how to use the Microsoft WebView2 control to automate HTML to PDF generation generically for any kind of Windows application, including services. We'll look at the WebView and it's printing functionality and some of the intricacies that are involved in hosting the WebView control outside of a desktop application context to provide unattended mode even in service context.
Programmatic Html to PDF Generation using the WebView2 Control with .NET
In this post I describe how to use the Microsoft WebView2 control to automate HTML to PDF generation generically for any kind of Windows application, including services. We'll look at the WebView and it's printing functionality and some of the intricacies that are involved in hosting the WebView control outside of a desktop application context to provide unattended mode even in service context.
Comparing Raw ASP.NET Request Throughput across Versions
When I set up a new machine I usually use a small ASP.NET test project to get a feel of performance of the machine and when that happens I also take a moment to compare performance across recent versions of .NET to see how things are improving - and improved they have.Both due to the new hardware I'm using but also ASP.NET continues to bump up performance in every new version that comes out.In this post I describe a simple project with minimal do nothing requests to test the ASP,.NET pipeline locally and how to test these request as well as discussing the results.
Reading Raw ASP.NET Request.Body Multiple Times
Some time ago I wrote about accessing raw request body content in ASP.NET Core which ended up being one of the most popular posts on this blog. But I failed to mention one major caveat: By default Request.Body can only be read once. In this post I discuss why frequently when you need raw Request.Body access you actually need to read the body more than once, and you can enable that functionality and deal with the caveats of doing so.
Sharing Tab Missing in Windows 11 Folder Properties
For some unfathomable reason, Windows 11 has removed the Sharing Tab on the Explorer Properties Context menu by default. The Sharing Tab allows you to shared folders and drives for remote access. In this post I discuss how to get the Sharing Tab back and also touch on how to make sure your machine can actually accept remote connections so you can share your folders and drives.
Sharing Tab Missing in Windows 11 Folder Properties
For some unfathomable reason, Windows 11 has removed the Sharing Tab on the Explorer Properties Context menu by default. The Sharing Tab allows you to shared folders and drives for remote access. In this post I discuss how to get the Sharing Tab back and also touch on how to make sure your machine can actually accept remote connections so you can share your folders and drives.
Working around the WPF ImageSource Blues
The WPF Image control and its ImageSource property can be problematic if you are loading a lot of images in a list. Depending on where you load images from, and how, you can very easily get bogged down with slow, blocking load operations, and memory leaks when the controls are released. In this post I describe a couple of specific problems I ran into loading a sizable list of images from files and show a few ways how to avoid the potential pitfalls related to ImageSource peculiarities.
Integrating OpenAI Image Generation into a .NET Application
Image Generation AIs are proving to be very good at creating images that can be used for all sorts of purposes. In this article I discuss how you can integrate image generation right into your own .NET applications using the OpenAI REST API. In addition I'll show how you can integrated this functionality into a larger application and discuss some general thoughts on image AI usage based on some of the experiences from a developer/non-designer user perspective.
Integrating OpenAI Image Generation into a .NET Application
Image Generation AIs are proving to be very good at creating images that can be used for all sorts of purposes. In this article I discuss how you can integrate image generation right into your own .NET applications using the OpenAI REST API. In addition I'll show how you can integrated this functionality into a larger application and discuss some general thoughts on image AI usage based on some of the experiences from a developer/non-designer user perspective.
Embedding a minimal ASP.NET Web Server into a Desktop Application
Did you ever need to embed a Web Server into a non-Web application? In this post I describe how you can use host ASP.NET in a non-Web application and specifically in a WPF desktop app. What do you need, how is it different and some of the issues that you need to consider if you want to use ASP.NET in your non-Web applications.
Embedding a minimal ASP.NET Web Server into a Desktop Application
Did you ever need to embed a Web Server into a non-Web application? In this post I describe how you can use host ASP.NET in a non-Web application and specifically in a WPF desktop app. What do you need, how is it different and some of the issues that you need to consider if you want to use ASP.NET in your non-Web applications.
Save Files With Elevated Permissions on UnauthorizedAccessException
If you have an application that generically allows you to edit and save files, you might on rare occasions need to save files in locations that where a regular user account does not have permissions to save. Rather than failing wouldn't it be nice to let the user know and optionally allow saving with elevated permissions? In this post I describe the workflow and implementation on how to do just that.
Caching your WebView Environment to manage multiple WebView2 Controls
I've been struggling with rare WebView initialization errors in one of my applications, that have been difficult to debug and track down. After a lot of trial and error I discovered that the problem is related to WebView Environment instantiations that might be stepping on each other. In this post I describe the problem and a solution that involves creating a single WebView Environment and reusing it for all WebView initialization.
Rolling Forward to Major Versions in .NET
.NET Core has sophisticated policies that allows your applications that are compiled to specific versions of the .NET Runtime can roll forward to newer versions. You can specify what part of the version to roll forward and that generally works well, except for preview releases which require an extra step.
IIS Error 500.19 with ASP.NET Core Application
Running on IIS locally is pretty rare, but if for some odd reason you decide to run IIS locally on your dev machine you might find yourself getting a 500.19 error which relates to an issue in the web.config configuration. The solution is simple enough: Make sure the ASP.NET Core Hosting Module is installed. In this post I describe in more detail what the problem is and why you need a seemingly superfluous extra install to get IIS and ASP.NET Core to cooperate on local dev machine.
IIS Error 500.19 with ASP.NET Core Application
Running on IIS locally is pretty rare, but if for some odd reason you decide to run IIS locally on your dev machine you might find yourself getting a 500.19 error which relates to an issue in the web.config configuration. The solution is simple enough: Make sure the ASP.NET Core Hosting Module is installed. In this post I describe in more detail what the problem is and why you need a seemingly superfluous extra install to get IIS and ASP.NET Core to cooperate on local dev machine.
Dotnet Tool Component not found on the Mac
I've run into this problem a few times: I install a new Mac OS and then install the .NET SDK. A bit later I install a dotnet tool using `dotnet tool install -g` and then try to run it, only to find out that the SDK is not able find it. This post is a note to self on how to fix the pathing for .NET tools to be found correctly and to be able to run your dotnet tools.
Map Physical Paths with an HttpContext.MapPath() Extension Method in ASP.NET
ASP.NET Core doesn't have a Server.MapPath() method as classic ASP.NET had, and getting at the root path in Core is a little bit more involved than in those older versions. In this post I describe how to find the application Content and Web root folders and describe a MapPath() helper that simulates the old behavior.
A WPF Statusbar Control
Statusbar controls are boring, but because of the way that they are used there are a number of caveats like ensuring the UI updates even in linear code, allowing for timeouts of status messages and resetting to default, and to provide some visual clues to draw attention to the status messages displayed. In this post I talk about a custom status bar control and helper that make it super easy to use a new status bar control or attach additional functionality to an existing status bar.
Getting the .NET Desktop Runtime Installed with a Custom Runtime Checker and Installer
I've recently moved my Markdown Monster Desktop Application to .NET 7.0 and I had to make a decision on how to get the Runtime installed or packaged with my application. In this post I review the different deployment modes, the plus's and cons and the solution I ended up with which was to build a custom install wrapper that can check and install the runtime if not already present from an Installer or interactively.,
Getting the .NET Desktop Runtime Installed with a Custom Runtime Checker and Installer
I've recently moved my Markdown Monster Desktop Application to .NET 7.0 and I had to make a decision on how to get the Runtime installed or packaged with my application. In this post I review the different deployment modes, the plus's and cons and the solution I ended up with which was to build a custom install wrapper that can check and install the runtime if not already present from an Installer or interactively.,
Getting .NET Library Projects to Output Dependent Assemblies
Recent .NET Core versions have changed how .NET Core Library projects output dependencies into the build folder. The new behavior doesn't output depdencies, unlike full framework .NET projects which always automatically dumped dependencies into the build output folder. This isn't a common requirement, but when you need it, the options are sufficiently obscure and this post discusses how you can make your dependencies output into the build folder
Implementing Two-Factor Auth using an Authenticator App in ASP.NET
Two factor authentication using Authenticator apps is getting more popular.One advantage of Authenticator 2FA is that you don't need to use a service nor do users have to provide additional bits of personal information.In this article I describe how Authenticator based 2FA works in the context of an application without using ASP.NET Identity.
Removing the IIS Server Request Header from ASP.NET Core Apps (any version)
ASP.NET Core applications that run on IIS as InProcess output an Server name for IIS into the HTTP headers. If you want to remove the server header, you'll find that the process for IIS is different than for the internally created Kestrel header and you can't use the same approach to remove the header as with Kestrel applications. In this post I discuss why the header behaves differently in IIS and how to remove it regardless of ASP.NET version.
Sending and Receiving GMail Email Attachments that contain Code or Binaries
As a developer, you're likely to occasionally send an email with attachments that are either code or binary executable files either as straight files or in a zipped up collection of code or binary files.You'll find that you can't actually send certain types of files or even files embedded in archives and even encrypted archives as most mail servers these days scan file content both before sending and when receiving email.In this post I discuss what works and what doesn't and how you can work around those files that don't work.
Setting an Absolute Output Path for .NET SDK Projects
By default .NET SDK project dump their final build output into a deeply nested folder structure that describes the build configuration, target, platform and sometimes additional package folders. While that's useful especially for multi-targeted projects. Sometimes you just want your output to go to specific folder without all that noise. In this short post I show you what you need to set in your project file to put your files exactly where you tell them to,
Preventing iOS Textbox Auto Zooming and ViewPort Sizing
If you've build mobile Web applications that need to run on iOS Safari and on an iPhone you might have run into the problem of input fields 'auto-zooming' the display when the input field and popup keyboard get focus. The view zooms and doesn't return back to the unzoomed even after exiting the input field. In this post I describe why this happens in some scenarios, and a couple of ways you can work around this annoying iOS Web browser behavior.
Using Application Insights in .NET Desktop Applications
Using Application Insights with desktop applications isn't the most obvious operation, as App Insights has been primarily designed as a tool for providing logging, statitics and exception report for Web based applications. However, with a little bit of reworking it's actually quite straight forward to use Application Insights with Desktop applications and in this post I show you how I integrate App Insights in my WPF applications.
WkHtmlToPdf: Dealing with broken Url Encoded and Extended Character Links
WkHtmlToPdf is a commonly used tool to create PDF documents from HTML files or Urls. Unfortunately it's a bit cranky and one of the problems you can run into is that links that include URL encoding won't work in your output PDF. In this post I describe the problem and a hacky workaround to make broken PDF links work by hacking the HTML file prior to conversion.
Async Event Methods and preventDefault() in JavaScript
When using async events, it's important to understand how events work when called asynchronously. Specifically if you need to interact with the event context for things like preventDefault(), cancelBubble() or returning values that determine completion state, you need to be careful as these may have no effect if called after an `await` call.
UpperCase Styling via CSS and text-transform
I learned something new today: there's a CSS `text-transform` style property that can be used to transform text automatically to upper, lower or capitalized case. No JavaScript contortions and it just works. In all my years doing Web dev I've not run into this property before, so I'm posting it here for others to find as well...
A Button Only Date Picker and JavaScript Date Control Binding
The native date picker in HTML is a bit of a pain to work with as it's overly simplistic in features and how you have to assign and retrieve values from it.It also isn't customizable so if you need to build custom behavior like a button date popup that doesn't show the input control, you're out of luck.In this post I discuss the challenges of the HTML date picker control, provide small component to make binding values easier, and provide an example on how to create a button only date picker both with plain JavaScript and as a small Vue component.
Basic Windows Machine Hardware information from WMI for Exception Logging from .NET
When writing out error information for a desktop application to a log whether local or to a telmetry engine, it's useful to get some idea of what hardware the app is running on.WPF applications in particular can have odd behaviors that are related to hardware acceleration, running inside of a VM or particular video drivers.In this short post I show how you can get very basic machine and GPU information that provides information on these basic system stats that can prove useful to trackdown rare hardware related issues.
Windows Audio Encoding Failure after Settings Change
Ran into a problem with Windows Audio not playing for MP3, WAV and other music files as well as some applications like Spotify. Any audio playback ended up resulting in an error related to an invalid encoder. Turns out the problem was an unexpected settings change. Here's the scoop.
HTML Table Cell Overflow Handling
HTML table column wrapping and truncating doesn't work like other HTML elements. Specifically if you want to keep table column content from wrapping via `overflow` or `white-space` wrapping settings you'll find that tables just laugh in your face. Here's a quick post that describes table wrapping and text truncation issues and the hacky workaround.
Fix that damn Git Unsafe Repository
As of Git 2.36.2 Git has a new security feature that won't allow running Git commands until the folder the repository lives in is 'trusted'. This can be annoying, but it's relatively easy to fix. In this post I look at what causes the issue and show a number of ways that you can use to trust the repository to get on with life...
SetResolution: Setting Windows Display Resolution from the Terminal
I recently switched to a single 4k monitor and had a need to quickly switch resolutions to avoid the UI hostile Windows Display Resolution widget in Settings. I ended up creating a small command line utility called SetResolution that lets you quickly and easily set a new Resolution, create profiles of resolutions to switch to.
Avoid WebDeploy Locking Errors to IIS with Shadow Copy for ASP.NET Core Apps
If you're self-hosting ASP.NET Core applications on IIS and using WebDeploy to publish to the server, you've very likely run into the dreaded locked file problem on the server. In this post I show you how you can work around locking problems with the base WebDeploy configuration and by using a new experimental feature in ASP.NET 6.0 to Shadow Copy deploy binaries. As a bonus this post also describes setting up and using Web Deploy in some detail.
HSTS: Fix automatic re-routing of http:// to https:// on localhost in Web Browsers
If you're doing local Web develop with multiple development tools you've probably run into a problem where you end up not being able to access a local site via unsecured `http://` requests and automatically get redirected to `https://` no matter what you try.If you don't have a certificate set up for the site you may not even be able to access the site at all.In this post I discuss how HSTS works and why it can be a problem for local development as well as how to clear out the HSTS cache or avoid using it locally.
Testing HttpRequest.Form Variables in Unit Tests for ASP.NET Core Components
Here's a quick post that shows how to create a testable HttpRequest.Form collection so you can test form variables in a unit test.