12 February 2019 08:26
Exceptions in .NET represent an error condition in an executing program. Error conditions can come about as a result of a large number of causes, each represented by its own exception type. Most exceptions arise from logical errors in code, such as an attempt to work with an object that has not been instantiated (
NullRefrenceException), or to divide by zero (
DivideByZeroException). Other types of exceptions result from technical issues, which may or may not be temporary. Examples of such issues might include a database or mail server being unavailable, or insufficient file system permissions.
17 October 2018 13:32
Razor Class libraries (RCLs) were introduced in ASP.NET Core 2.1 as a way to package and distribute UI components to be referenced and consumed within a host application. You can see them as a fully functioning part of a web application packaged as a class libray. The templated management pages for ASP.NET Identity were included as a Razor Class Library in the project template in 2.1. The Identity UI RCL includes the Razor pages, Filters, a stub EmailService class that Identity uses, and local versions of both Bootstrap 3 and 4.
10 October 2018 08:35
This article builds on the simple paging functionality that was added to a Razor Pages application in my last article by showing how to add sorting functionality so that the user can determine the order in which results are displayed.
03 October 2018 07:49
This article attempts to demonstrate how to implement simple paging functionality in a Razor Pages application. I will explain the basics behind paging, and then use BootStrap 4 to render a variety of paging links, without resorting to Nuget packages for link generation.
26 September 2018 07:39
At its heart, the Razor Pages routing story is a simple one. It uses a convention of mapping URLs to files on disk. There are ways to customise how pages are found on an individual basis, but what if you want to change the default convention in its entirety? There is also a way to do that. And it's quite simple, as this article will demonstrate, using two real-world examples.
17 September 2018 08:17
There are a few demonstrations showing how to use the jQuery Unobtrusive AJAX library in ASP.NET Core, but existing examples tend to feature MVC applications. This article looks at how to use Unobtrusive AJAX in a Razor Pages setting, where it will help to remove a lot of the boilerplate associated with making AJAX requests.
07 September 2018 15:57
Updating portions of a page using AJAX and partial views is a routine task in ASP.NET MVC applications. The experience is little different in ASP.NET Core Razor Pages - not much, but enough to stump some people. Here is some advice on accomplishing this task, and a preview of some additional help coming in the near future.
03 September 2018 08:01
Support for Areas was added to Razor Pages with the release of ASP.NET Core 2.1. They have long been used in MVC applications as a way to separate logical chunks of large applications into semi-independent modules to facilitate team working etc. Here, I explore how to use areas in a Razor Pages application.
29 August 2018 08:23
Support for filters was added to Razor Pages with the release of ASP.NET Core
2.1. Filters, for those unfamiliar with them, are components that enable the
injection of processing at certain points within the Razor Page lifecycle.
They differ from Middleware in that they provide access to the
Razor Pages offers
a number of different filter options. One
of the things that you might want to do in a filter is to obtain data from an
external resource (database, web service etc) and then use it in the
PageModel or ViewData. Here, I take a look at how you can access the model or
ViewData dictionary depending on the type of filter implementation that you choose.
15 August 2018 13:46
Query Types, introduced in Entity Framework Core 2.1 enable you to return non-entity types that map to tables or views and can serve as the return type from FromSql method calls.
16 July 2018 07:54
In this article, I look at the steps required to get TypeScript up and running in the context of a Razor Pages application. I discuss why you might want to do this, and I use Knockout for the purposes of demonstration. By the end of the article, I will have configured and used TypeScript to replicate part of the final code for the Single Page Application tutorial from learn.knockout.com.
05 July 2018 13:27
In my last article, I looked at the experimental Blazor framework, using Cascading Dropdown Lists as an entry point. Since then, some feedback from Steve Sanderson to a question I asked has shown me a better way to implement this pattern.
24 May 2018 20:51
21 May 2018 13:49
UI generation and processing within web applications is moving increasingly to the client. Data processing and storage is still undertaken on the server, with JSON being the preferred format for exchanging data between the server and the client. There are a number of ways in which you can generate JSON when working with Razor Pages. This article explores some of them.
26 March 2018 08:50
Most migrations that you execute when working with Entity Framework Core are likely to be straightforward - resulting in nothing more than an adjustment to the database schema. Sometimes, however, you might also want to include a task that requires longer than the default command timeout value (30 seconds in SQL Server) such as importing a lot of data.