Model Binding has been a popular feature of ASP.NET MVC, but has, before now, had some minor restrictions. ASP.NET Core now has enhanced model binding: If a value passed via routes, posted data, or query strings couldn't be bound appropriately, it forced a global exception. Now, there are a number of ways of providing a more graceful reaction to incorrect data. You can now force the binding to a given source or create new sources for binding to. Dino Esposito explains.… Read more
We all have our favourite third-party extensions to Visual Studio, and although we all like Resharper, there are many others that could well make your development work easier. To celebrate the fact that Visual Studio Enterprise now includes ReadyRoll Core, SQL Prompt Core, and SQL Search as part of the Data storage and processing workload, Michael Sorens describes nine of his current favourite extensions, and wonders if he's missing anything in his list.… Read more
Scala and Apache Spark might seem an unlikely medium for implementing an ETL process, but there are reasons for considering it as an alternative. After all, many Big Data solutions are ideally suited to the preparation of data for input into a relational database, and Scala is a well thought-out and expressive language. Krzysztof Stanaszek describes some of the advantages and disadvantages of a scala-based approach to implementing and testing an ETL solution. … Read more
Entity Framework (EF) is Microsoft’s Object/Relational (ORM) database access library, with a new generation, EF Core, released in 2016. In this article Jon P Smith looks at six different software principles and patterns that help to keep the EF code nicely separated from the rest of the application. The six approaches make the EF database access code is easier to write, test, refactor and, most importantly, performance-tune.… Read more
Model binders work under the covers in ASP.Net MVC to provide the data for the action methods on a controller class. This data is held by the incoming HTTP request embedded into POST-ed form values, and maybe even the URL itself. Much magic is performed to get this right and, with some care, you can ensure that you can bind to object data, arrays and collections, as well as providing default values.… Read more
When Google announced the 'Go' language in 2009 we were all underexcited. After all, a compiled, statically typed language in the tradition of Algol and C isn't that radical, especially one that eschewed generic programming, implicit type conversions, assertions, inheritance and pointer arithmetic. However, it has proved to be robust, highly-portable, simple to use, and productive to work with. Ed Elliott reckons that it is definitely worth checking it out. … Read more
Data grids are easy to do in HTML, and if we want anything complicated in terms of scrolling, locking and data entry, we usually shrug and buy a component to do it. However, there is a lot to be said for the approach of creating tables using a basic JavaScript platform such as jQuery, perhaps using a plugin which you can then customise. Dino talks you through this approach, showing how to take the DataTables plugin and implement locked columns, on-demand paging and filtering.… Read more
User Acceptance Testing (UAT) is an important part of the development process. If carried out as early as possible and as regularly as possible, it not only alerts the development team to aspects that don't yet meet the requirements of the users, but also gives governance a better idea of progress. If UAT is delayed, defects become expensive and troublesome to fix. Sophia Segal gives an experienced summary view of UAT… Read more
Node.JS and SQL Server are a good match for creating non-blocking, event-driven database applications. Though you can use ODBC or JDBC to communicate between the two, it is possible to run such applications on platforms such as Azure, Linux, OSX and iOS by using Node together with the JavaScript TDS library called 'Tedious'. 'Tedious' is a mature product but it is still possible to get things wrong in converting SQL Server datatypes such as BigInt to native Javascript data. … Read more
There are many ways that static code analysis can help to speed software delivery. It can pick up, as a preliminary to check-in, errors and weaknesses in code that can happen incidentally to even the most experienced developer. It can give the team a measure of technical debt, and remove the obvious 'noise' from code before it is reviewed. Vishwas introduces a popular Code-quality inspection tool, SonarQube, and takes you through the basics of using it with C# and Java. … Read more
Amazon's Simple Workflow Service (SWF) in AWS provides a model of workflow that is simple to understand but is it simple to get a robust and durable workflow in place? Tom Fischer guides you through the bewildering early stages of your first SWF application, and concludes that workflows inherently take time and effort to get right, but SWF provides a formidable cloud-based solution … Read more
The design of ASP.NET includes the valuable session variables that enable the application to keep track of individual sessions. Unfortunately the ASP.NET pipeline will not process requests belonging to the same session concurrently but queues them, and executes them serially. MVC locks session variables to ensure thread safety and concurrency control, but takes a conservative approach to polling for these locks. Do you always need this level of thread safety? If not, what can you do to improve performance when you need to use writeable session variables?… Read more
Even though we're less inclined to print web-pages nowadays, it often makes sense to save useful content from a website as a PDF file to read offline. Dino Esposito explains printing from ASP.NET MVC. … Read more
All sorts of complex data can be represented as a string but that doesn't mean you can treat them merely as strings. There are so many things that can go wrong if you assume that generic string operations such as concatenation can serve to create complex markup, expressions, codes and serialised objects. It pays instead to create dedicated builders for any such complex data that you may need to create. Michael Sorens explains some defensive coding to make for a more robust application.… Read more
If you are developing a web application, almost every design decision you make can introduce a security flaw if you get it wrong. Although attacks are becoming more common, and more widely reported, the same common errors continue to provide the most opportunities for hackers. OWASP provides a 'top ten' security problems. Vishwas here describes them and explains how to avoid them… Read more
There is a pragmatic approach to error handling in ASP.NET MVC. This is the idea of recovering gracefully from those unhandled exception errors where remedial action cannot be taken under the current context, by passing control to a specified URL that is designed to deal with a particular category of application-specific error. Dino Esposito elaborates on a pattern that prevents unhandled exceptions from bubbling up well beyond the intended sco… Read more
LINQ is certainly extraordinarily useful. It brings the power of query expressions to C#, allowing an easy way of getting the data you need from a variety of data sources. Up to now, there hasn't been a VS debugger for LINQ that gives you the means to visualise the data at every point in the chain. Michael Sorens, a keen LINQ user, describes a third-party tool that now promises to make using LINQ something we can all participate in.… Read more
In ASP.NET MVC, Razor Views contain the HTML layout and the code that is combined with the data to be displayed in the final HTML. Dino continues his description of Razor Views by describing more advanced uses such as overridable views in multi-tenant applications and in-memory compilation of Razor templates to strings. … Read more
You've written a superb, clever, application that you are trying to encourage your colleagues to use. They're not interested. Why? You've neglected the documentation. Surely, the saying goes 'Build a better mousetrap and the world will beat a path to your door'? Nope, not without comprehensive and complete documentation and marketing, it won't. Documentation is the secret of ensuring that good software will succeed. … Read more
Windows hasn't had a package manager in the style of the Advanced Packaging Tool (APT) of Linux distributions. Apt-get is a great way of installing packages and other software. We have Chocolatey, of course which has a growing library of software and even allows you to automatically update software. Now PowerShell has an 'official' way of using any system, such as NuGet, Chocolatey, GitHub or PSget. It is definitely useful and likely to mature into an indispensable tool for Windows users. Nicolas explains why… Read more