Troubleshoots the ASP.NET Core "White Screen of Death" startup failure with concrete fixes: temporarily forcing UseDeveloperExceptionPage in production, then wiring ConfigureLogging with AddEventLog or an elmah.io sink to surface the real error. ...
Thomas Ardal
Meet Thomas, the founder and developer behind elmah.io. Thomas blogs about everything technical from C# and ASP.NET Core to machine learning.
HTTP Error 500.30 - ASP.NET Core app failed to start help
How to authorize and post Slack messages from ASP.NET Core 💬
Implements Slack's OAuth v2 flow in an ASP.NET Core MVC app: an AuthorizeSlack action redirecting with the incoming-webhook scope, a SlackCallback action exchanging the code via oauth.v2.access, and storing the returned webhook URL to post messages. ...
Upload and resize an image natively with ASP.NET Core 🖼️
Resizes an uploaded IFormFile to 256x256 using only System.Drawing.Common's Image.FromStream and Bitmap classes - no ImageSharp needed - then saves the bytes to disk with a FileStream as a simple alternative for basic scenarios. ...
Show a name and profile photo with .NET and Gravatar 🤵
Shows a Gravatar avatar from just an email address using an MD5 hash extension method and the gravatar.com/avatar/HASH URL, including a robohash fallback for missing accounts, then calls Gravatar's JSON API from C# to fetch name and photo data server-side. ...
Introducing Breadcrumbs
Announces elmah.io's new Breadcrumbs feature with launch-day support in Elmah.Io.AspNetCore, Elmah.Io.JavaScript, and Elmah.Io.Xamarin, showing manual AddBreadcrumb calls plus the TreatLoggingAsBreadcrumbs option for automatic Microsoft.Extensions.Logging capture. ...
Create a colored CLI with System.CommandLine and Spectre 🎨
Builds FART (File Association and Rename Tool), a sample CLI using System.CommandLine's RootCommand and nested rename Command with required --input/--output options, then layers in Spectre.Console for colored terminal output. ...
Adding CAPTCHA on form posts with ASP.NET Core 🚦
Adds reCAPTCHA v2 to an ASP.NET Core Identity ForgotPassword.cshtml page to block bots from mass-triggering reset emails: scaffolding the page, embedding the g-recaptcha widget with a site key, then verifying the token server-side through a wrapped HttpClient. ...
Pretty print/syntax highlight .NET stack traces in a browser ✨
Turns an unformatted .NET stack trace in a pre/code block into pretty-printed, syntax-highlighted output using the jQuery-based netstack.js library and its st-type, st-method, and st-file CSS classes for custom styling. ...
Subscribe users to a Mailchimp newsletter from .NET/C# 📧🐵
Adds a newsletter checkbox to ASP.NET Core Identity's Register.cshtml, wiring the MailChimp.Net.V3 package's IMailChimpManager to call Members.AddOrUpdateAsync with Status.Subscribed or Pending for double opt-in, plus notes on handling API timeouts. ...