All Posts in 2019


Building a .NET Core URL Forward Service

I recently built a URL forward service named “Link Forwarder” using .NET Core 2.2. It’s open source and currently having a preview version deployed to my subdomain “go.edi.wang”. This article will share how I built it and what I learned. To help you understand the system and walk through the code, please check my GitHub repository for this project: https://github. …


IP Rate Limit for ASP.NET Core

In websites or API applications, we often want to block high-frequency requests in a short period of time for an IP to prevent boring people or malicious attacks. In ASP.NET Core, limiting the request rate of IP is now super easy, let's see. AspNetCoreRateLimit There's already a nice library for limiting request rate, called AspNetCoreRateLimit. GitHub: https://github.com/stefanprodan/ …


Reset Azure Blob Storage Content Type in .NET Core

My blog is using Azure Blob Storage to store images for posts, however, it went wrong these days when I am trying out Azure CDN, the cause is all my images requests are returning incorrect content-type. Let's see how to reset content type for files in Azure Blob Storage via .NET Core. When I uploaded images using the Azure Storage API for .NET, by default, without setting ContentType, which is …


SQL Server Export Data Tier Application via Command Line

We can use SSMS to export data tier application for an SQL Server database. I've been using this method for several years on my local machine. For those who don't know what's a DAC, you can refer to Microsoft document: "A data-tier application (DAC) is a logical database management entity that defines all of the SQL Server objects - like tables, views, and instance objects, including logins - …


Stop Generating Designer.cs for .resx files in .NET Core

In Visual Studio, if we add a Resource File (.resx) to a .NET Core project, you will find a ".Designer.cs" file is automatically generated and updated whenever the resource content changes. This file basically contains auto-generated code for accessing resource values by key. In my blog system, I use the Resource File to maintain the default configuration data when setting up the blog for the …


How to Pack a .NET Core Class Library and Upload to NuGet

NuGet is the package manager of the. NET world, we can both use official website nuget.org, or build our own corporate and private servers. Now, with . NET Core, it's easier than ever to pack and upload a NuGet package, let's take a look! NuGet Account If you want your package to be used by every .NET developers in the world, then you need to have a nuget.org account to upload your own …


Send Email in .NET Core via MailKit

The ability to send e-mail notifications is common in a variety of systems. My blog can also send emails to administrators when there are new comments, new replies, or when articles are referenced by other sites. So in. NET Core, how can we send an e-mail? My case will use Microsoft Outlook.com's personal account to send e-mail, using the SMTP protocol. But you can also do it with other SMTP- …


Use Environment Specific nlog.config in ASP.NET Core

ASP.NET Core has built-in aspsettings.env.json which can automatically apply to different environments. But how about NLog? In official examples, it only got one nlog.config file which will be used in all environments. Let's see how we can change it to use different config files on different environments. Why do we need this This requirement actually came from this blog system. My blog runs …


Operate Git with .NET Core

Git is the preferred source code version control tool for many programmers, and I've recently switched from TFVC to Git. I am going to show you how to operate Git with .NET Core. Why am I doing this First of all, we do have a lot of good Git clients, such as GitHub for Windows, VS/VS Code, git GUI, and so on, all quite mature, there is no need for us to reinvent this wheel in own. NET/C#. But …


Restart an ASP.NET Core Application Programmatically

We developers won't have access to servers all the time, and without management capabilities, it will be difficut to restart a web application. However, in ASP.NET Core, there is a way for us to programmatically restart our application without requring management capabilities from server admins. IApplicationLifetime There is a IApplicationLifetime interface in ASP.NET Core which can handle …


Read and Write Windows Registry in .NET Core

Yes, you read it right! It's totally possible! Even .NET Core is designed to be cross platform, but it does not mean you can not use platform specific APIs. Take Windows Registry for example, although .NET Standard can not contain Windows API like this. But there's still a way to use Windows Regisitry in .NET Core Applications. But first, you should be absolutely clear, that using platform …


Incremental Build Number for .NET Core via Azure DevOps

People familiar with the. NET framework know that we can let the compiler self-increase the version number by specifying AssemblyVersion as 10.0.*. But. NET core and. NET Standard are not. Even with open source projects like MSBump, there are certain flaws. Typically, such requirement happens on a CI/CD server. Let's take a look at how to easily handle it with Azure DevOps. About Versioning in . …


Send Email After Release Deployment in Azure DevOps

By default, Azure DevOps sends an email notification to team members after the compilation succeeds or fails. But in a CI/CD environment, we are more concerned about when the deployment is complete and then conducting manual or automated testing. Let's take a look at how to get Azure DevOps to automatically send mail notifications to team members after a successful deployment. Enter Project …


Fix .NET Core Website Failure After Deployment from Azure DevOps

I met a strange problem recently. After configuring the CI/CD pipeline with Azure DevOps and automatically deploy to Azure App Services, the. NET Core Website failed to start. Let's see how we can solve this problem. Find the issue First of all, fortunately, this is a staging environment. I found that the site unexpectedly did not log anything, even log directory cannot be found, which is …


Fix Azure DevOps TF14045 Error When Deploy to Azure

I encountered an error when I try to setup CI/CD in Azure DevOps, I tried to deploy a .NET Core application to Azure App Service, but Azure DevOps won't connect to Azure. This is a known issue for Microsoft. Let's see how we can manually setup a connection between Azure DevOps and Azure to workaround this issue. First, the error message I met was: Failed to get resource ID for resource type ' …


Detect Text Language using Azure Cognitive Services in .NET Core

There are many ways to identify what is the language of a text, in this era of AI, we can also add AI capabilities to our own application. I will show you to see how to use the AI Cognitive Service provided by Microsoft Azure to detect the language of a text. The prerequisite is that you will need an Azure subscription. Create Azure Cognitive Services Account Click "Create a resource", then …


Recommended Visual Studio Configuration for .NET Core Development

Visual Studio has always been a good friend to .NET developers, although VS Code can do .NET Core development, VS is still having a lot advantages. Let's see how to make Visual Studio more handy for .NET Core development. Basic Configuration First, please be advised, not all versions of Visual Studio supports .NET Core development, even some early version of VS2017. Some people may mistake …


ASP.NET Core Dependency Injection in ActionFilterAttribute

In ASP.NET Core, we can easily use constructor injection to make Dependent Injections on components such as Controller and ViewComponent. But how to do it with ActionFilterAttribute? The Problem My blog system has an ActionFilter for deleting subscription files, and I want to log errors when an exception happens. I use NLog as the logging component, so I need to use LogManager. …


Caveats in ASP.NET Core Data Protection

ASP.NET Core provides a built-in Data Protection mechanism to let us encrypt or decrypt sensitive data. There are some limitations that can cause problems while bringing convenience. I met some problems these days. My Scenario My blog system has a feature to send email notifications, so you need to configure an email account to let the program use that account to send mail to an administrator …


Auto Refresh Settings Changes in ASP.NET Core Runtime

In ASP.NET Core, if you modify the settings in appsettings.json, you will have to restart the site to take effect. Is there a way to refresh and apply it automatically after you modify the settings? Background Let's take a look at a website created by ASP.NET Core default templates. It includes two settings files: appsettings.json appsettings.Development.json The former one is used in …