There are many ways to generate PDF files. You can use a PDF library, but generating a PDF manually is not trivial. You can use a report library, but they are often paid solution and not trivial to use for simple needs. In this post, we'll use an html template and Playwright to generate a PDF file. Using a browser to convert an html file to a PDF file is very convenient as it allows to use all html/CSS… [read more]

I recently had to investigate an infinite loop in an application. A simplified version of the buggy code is like that: static void Main() { bool isReady = false; var thread = new Thread(_ => { // ... (initialization) isReady = true; // ... (code after initialization) }); thread.Start(); // wait for the other thread to do some initialization while (!isReady) { // code omitted for brevity }… [read more]

This post is the result of a code review. The code I'll show is a simplified version of the original code, so the bug is easier to spot (or not). The goal of the code is to read a UTF-8 encoded string from a stream. In the actual context, the stream is a named pipe and there are a few more things to do with the stream. string ReadString(Stream stream) { var sb = new StringBuilder(); var buffer = new… [read more]

We often use NuGet through Visual Studio or dotnet CLI, but you can also use the same using your own application. In this post, I'm going to show multiple examples of using the .NET client library for NuGet. To start using the NuGet client library, you need to add a reference to the NuGet packages: <ItemGroup> <PackageReference Include="NuGet.Protocol" Version="5.10.0" /> <PackageReference… [read more]

Reproducible builds are important when building NuGet packages from public sources. Indeed, it gives your consumers confidence in your packages by allowing them to validate the package has actually been built using the public sources. To be able to reproduce a build, you need the source files, the referenced DLLs, the compiler version, and the compiler options (language version, defines, nullables, etc.)… [read more]

If you want to improve the performance of a Blazor application, you may want to reduce the number of time the UI is recomputed. In Blazor, this means reducing the number of time the StateHasChanged method is called. This method needs to be called only when the state has changed and the UI needs to be updated. However, there are multiple ways to implicitly call it. One of them is to handle an event such as… [read more]

GUIDs are commonly used as a key in a database. If you want to create a URL to a specific record, you may want to use the GUID in the URL. Now you have a problem: how to display the GUID in the URL? The easy solution is to use ToString("N"), but this will return the GUID in the format 00000000000000000000000000000000. However, this format is inefficient. You can use ToBase64String to get the GUID in a… [read more]

In an ASP.NET Core application, you can configure the JSON serializer options used by controllers using the AddJsonOptions method: public void ConfigureServices(IServiceCollection services) { services.AddControllers() .AddJsonOptions(options => options.JsonSerializerOptions.PropertyNamingPolicy = null); } This works well for controllers. .NET 6 introduced minimal APIs for hosting and routing in web… [read more]

To upload a file you can use the FileUpload control. This control generates a <input type="file"> element and allows you to upload a file. To get a good user experience, you also need to support dropping files from the explorer or pasting images from the clipboard. The final result should look like this: First, you need to create a JavaScript file to register some events to handle drag and drop events and… [read more]

There are many cases where you want to smoothly remove an element from the UI. A solution is to use an animation to fade out the element before removing it. You can start the animation by adding a class to the element you want to remove. Then, you can use the transitionend or animationend event to actually remove the element. First, you need to register the transitionend event handler, so you can use it… [read more]