Edi Wang

.NET and Azure Developer

ASP.NET

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 …

.NET ASP.NET
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 …

.NET ASP.NET
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. …

.NET ASP.NET
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 …

.NET AJAX ASP.NET jQuery
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 …

.NET ASP.NET IIS
16
OCT

Get Client IP Address in ASP.NET Core 2.x

In classic ASP.NET we used to get client IP Address by Request.UserHostAddress. But this does not apply to ASP.NET Core 2.0. We need a different way to retrieve HTTP Request information. 1. Define a variable in your MVC controller private IHttpContextAccessor _accessor; 2.  DI into the controller's constructor public SomeController(IHttpContextAccessor accessor) { _accessor = accessor; …

.NET ASP.NET
06
APR

Configure Continuous Delivery for ASP.NET Core Website on Azure

Today I am trying new DevOps tools in VS2017 and Azure, my goal is to automate the process from development to production for an exsiting ASP.NET Core project. I have encountered some issues, and with the help of Microsoft Support, I was able to solve them and share with you guys. First, there are two ways to configure CD for Azure Web Apps. I prefer create a website first, then configure it from …

.NET ASP.NET Azure DevOps
09
OCT

Read AppSettings in ASP.NET Core 2.x

Today, I was rewriting an old ASP.NET MVC5 Demo project to ASP.NET Core, and found that the way we used to read Web.config by ConfigurationManager.AppSettings[] is no longer working. .NET Core has many new ways to achieve this. I picked one that suitable for my project. Here is how I do it. The Classic ASP.NET Code web.config Controller private static CloudBlobContainer GetBlobContainer() …

.NET ASP.NET
22
APR

如何高逼格读取Web.config中的AppSettings

先插句题外话，下版本的ASP.NET貌似把web.config撸掉了，都变成json了。所以本文讨论的内容可能以后用不到了，但是一些设计思想还是可以用的~ 直接进入正题，在ASP.NET网站里（也包括其他有web.config, app.config）的.NET工程里，读AppSettings的值是个很常见的场景。比如： 在代码里读的时候就会用到： ConfigurationManager.AppSettings["EnableAzureWebTrace"]; 这个[]索引器返回的是string类型。所以下一步我们通常需要类型转换才能在代码里拿来用。比如这个例子里，我们就要转换成bool。其他时候，可能要转换为int等类型。 string enableAzureWebTraceConfig = ConfigurationManager.AppSettings[" …

ASP.NET
18
JUL

Run Scheduled Tasks in ASP.NET Application

在ASP.NET里运行定时任务，这是个老生常谈的话题了，撇开那些用per request搞定屌丝办法，目前最好的解决办法只有2种： 1. 如果你有大微软的Azure，可以直接在网站服务中找到Jobs，自己看一下就会了 2. 如果你是屌丝，买不起Azure，就用本文介绍的WebBackgrounder搞 由于ASP.NET是服务器端Web框架，所以一般而言，一个操作的往往是只有收到客户端Request之后才能执行的，如果网站一直没人访问，没有Request进来，如何执行代码呢？定时任务就是这种坑爹场景。 还好，大微软的MVC帝、ASP.NET小王子haacked蜀黍给我们写了个 http://www.nuget.org/packages/WebBackgrounder/ 专门捣鼓这种场景。作为一个屌丝程序猿，和大牛的区别就在于“好编程，不求甚解”。所以我们不必在意它是怎么实现的，只要会用就行 …

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