31
DEC
.NET and Azure Developer
Posts in 2018
28
DEC
Dependency Injection with Multiple Implementations in ASP.NET Core
The built-in Dependency Injection (DI) in ASP.NET Core is very useful, but how do you deal with an interface has multiple implementations? Can the runtime choose one of these implementations based on configuration? Is there a way to get rid of reflection? Let me show you how to dynamically select a specific implementation of an interface at run time according to the configuration file without …
27
DEC
Path Caveat with ASP.NET Core 2.2 IIS Hosting
ASP.NET Core 2.2 has been in place for some time, with a new feature that can use the new AspNetCoreModuleV2 and deploy with InProcess mode on IIS to dramatically improve performance. These days Azure App Service finally completed the deployment of this new version of the module, I configured my blog to the new module, and it exploded in production. Let's see why and how to solve it. If you don't …
21
DEC
Automate Windows 10 Developer Machine Setup
One of the things programmers hate most is probably setup a computer. Because the programmer's computer environment configuration is very different from normal people. In general, it takes several hours to manually install a new development machine. Let this process automating, after all, the essence of programming is to let complex things simplify, find a way to be lazy! In fact, automatic …
18
DEC
Integrate Azure Application Insight Data into Your Own App
Microsoft Azure has a very powerful monitoring tool called Application Insights. It can monitor every aspect of our web application, including client and server metrics, error details, performance and so on. My blog is also using Application Insights, but everytime I want to see the data, I have to go to Azure portal, even for the basic metrics like page views or server response time. I want a …
15
DEC
2018 "Hour of Code" in Sanda University with Microsoft MVPs
Nowadays, computer technology is breaking the limits of human beings every day, bringing countless innovations. Getting more teenagers to learn programming techniques will bring more wonderful surprises to our world. With this in mind, on December 8th, the "Hour of Code" event was held in Shanghai Sanda University campus, sponsored by Microsoft China Public Welfare group. Three Microsoft MVPs …
13
DEC
Build .NET Core 2.2 Projects on Azure DevOps
.NET Core 2.2 has been release for couple of weeks. However, the build pipeline is still failing these days. Microsoft has not installed .NET Core 2.2 SDK to the hosted VS2017 agents yet. Let's see how to work around this issue and have a success build for our .NET Core 2.2 apps. 1. Add Task Edit your build definition, and click the "+" button to add a new task. 2. Add .NET Core SDK Installer …
25
NOV
.NET Core WebUtility.UrlEncode or HttpUtility.UrlEncode
When we are dealing with URL encode in .NET Core 2.1, there are two APIs: System.Net.WebUtility.UrlEncode and System.Web.HttpUtility.UrlEncode. What's the difference between them? And which one should we prefer to use? I have done some research today, here's my findings. 1. Test Results First, let's see some tests. I've tested 2 couples of the same method between WebUtility class and HttpUtility …
05
NOV
Build a Pixel Ruler with UWP
In certain applications, we may need an on-screen ruler that indicates pixels on the screen. However, the only built-in ruler in UWP is within the InkToolbar control, we are not able to use it elsewhere. So, I will teach you how to build a pixel ruler which can be used anywhere in your UWP applications. The Demo App Create a new blank UWP application called PixelRulerUwp with minimal runtime …
31
OCT
Migrating Old ASP.NET Applications to .NET Core
More and more people are talking about .NET Core these days. It is true that .NET Core is the future, and .NET Framework will still be maintained because very large number of applications can’t be migrated in a short time. .NET Core and .NET Framework are just like electric cars and gasoline powered cars. Gasoline cars is mature, and you can drive it without any problem, but electric cars have …
13
OCT
Generate Captcha Code in ASP.NET Core
If you want to use captcha code to protect your website from spam messages, there are a few options such as Google ReCaptcha and captcha.com. Both of them can be integrated into ASP.NET Core applications. However, you may still want to generate the captcha code yourself for some reason, such as your website may be used in mainland China... This post will show you how to generate and use captcha …
12
OCT
Add Watermark to Uploaded Image in ASP.NET Core
Adding watermark to an image is very widely used in websites in order to protect the content owner's copyright, such as a blog system like this website. In traditional ASP.NET (.NET Framework), we could use System.Web.Helpers.WebImage to add text watermark like this: var image = new WebImage(imageBytes); image.AddTextWatermark( Settings.Instance.WatermarkText, "White", Settings.Instance. …
09
OCT
Fix AcrylicBrush Missing on NavigationView in Windows 10 SDK 17763
Microsoft released a new version of Windows 10 UWP SDK Build 17763, you can check the What's New document for more details. But when I retarget my App to version 17763, something unexpected happens, the AcrylicBrush gone missing if I change my App runtime to version 17763. I am not sure if this is by design on 17763 or it is a bug, I am trying to contact Microsoft product group on this problem. …
27
SEP
Get App Version in .NET Core
We can define versions on our .NET Core applications, but how to get the version at runtime? There are several ways to do it. First, let's see a typical .NET Core project file with versioning. We can define the version numbers for AssemblyVersion, FileVersion and Version in the project file (.csproj). The AssemblyVersion and FileVersion attributes must be in format of "major[.minor[.build[. …
19
SEP
Send AntiForgeryToken via jQuery Ajax in ASP.NET Core
In ASP.NET Core, if we use jQuery Ajax to post data to the server, and we want the ValidateAntiForgeryToken attribute to work. We have to do some tricks. The official document didn't document how to do it via jQuery. Let me show you how to do it. Please do read the official document first: https://docs.microsoft.com/en-us/aspnet/core/security/anti-request-forgery?view=aspnetcore-2.1 In my …
18
SEP
Prevent Image Hotlinking in ASP.NET/Core Applications
Introduction As a website developer, we sometimes don't want the images on our own website to be directly referenced and showed on other's website. It can cause a lot network bandwidth for our datacenters in some cases, which means costing money for us to pay for the one who use our images. For example, your website is A.com, you have an image on http://a.com/facepalm.jpg and B.com used your …
31
JUL
How to Fix Extended TitleBar Overlapping NavigationView PaneToggleButton
In UWP Apps, we some times extend our main view into title bar to get rid of Windows 10 default title bar. However if you are using NavigationView under extended title bar, you will find your PaneToggleButton overlapped by the title bar. And the user won't be able to click on the upper part of the button because it is where the title bar need to respond to window drag actions. This image shows …
22
JUL
Windows Community Toolkit: Use CameraPreview to Take Photos
In UWP Apps, if we want to use the device's camera to take photos and save to a file, it is used to be some how complicated, the developer need to know about quite a lot things and also write quite a few code to get it down (As you can find the Camera examples from Microsoft offical sample code). In fact, in many cases, we just want to take a photo by the most easy and default options via the …
02
JUL
Read System Certificates in UWP
In Windows, we can view and manage the certificates using certmgr.msc, which is a system management console included in Windows itself. However, what if we want to view the certificates information in an UWP app? Here is the answer. First thing first, the method I use does not apply to UWP only. In fact it is from a WPF app I wrote. As Microsoft released .NET Standard 2.0, which allows me to …
19
APR
Send Feedback in UWP Apps by Windows 10 Feedback Hub
After our app has been put on Microsoft Store, there are a lot of ways to get users to send feedback, such as email, store reviews, or even write our own API collect feedback. But in fact, Windows 10 Feedback Hub can also be used to send feedbacks for our own Apps. Those who are familiar with Windows Insider know that when Windows 10 is installed, the system has a Feedback Hub, which is usually …
29
MAR
Customize Acrylic Brush in UWP Applications
Windows 10 Fall Creators Update (Build 16299) added acrylic brush, this is a UI brush that similar to Windows 7 Aero effect. A lot in box Windows Apps, such as Calculator are updated with the acrylic brush. However, the built in brushes will not always meet our own requirments. Especially when Windows automatically disable render of acrylic, such as low power mode, or with an inactive window, it …
24
JAN