Custom ASP.NET Web Menu Control – Part 1

There is often quite a bit of confusion when it comes to the topic of “custom controls” in the .NET 1.x world. This is mainly due to inconsistent naming conventions used on the different options available in Visual Studio .NET. Terminology such as user controls, web controls, custom controls, control libraries etc… being used to describe different development strategies makes it rather confusing to know exactly what type of control your application should use.

There are in fact 2 options for developing a “custom control” in ASP.NET. A custom control can be used to define either type, which simply means a control not provided by the .NET framework. The 2 options are: 1) Web User Control and 2) Web Control Library.

We’ll review each type in detail later on in the tutorial. This 2 part tutorial will focus on control type #2, a Web Control Library, which provides the greatest flexibility. This type of control is also the most confusing and difficult to implement.

To put this type of control into practical use we’ll build the control around a common topic of interest, which are navigation menus. The purpose of the control is 2-fold, create a reusable control that we can drag and drop onto any ASPX Web Form, and also to provide a completely customized programming experience and tailor the control to our specific needs of the application.

Part 1 of this tutorial will explore the differences between custom controls in more detail and create the framework for a Web Control Library in a sample ASP.NET application. We’ll explore the fundamentals of this type of custom control and demonstrate how to get the basic functionality of the menu working. In Part 2 we will advance upon this framework and build more aesthetics into the interface of the component as well as explore creating Design time properties to reduce code-behind logic.

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How to Cache Search Criteria in ASP.NET

How to Cache Search Criteria in ASP.NET

When developing nearly any application, one of the least considered aspects is unfortunately usability. Let’s be honest here, us developers are great at writing complex algorithms, designing database entity relationships and object oriented class structures, but when it comes down to the everyday user we often lose touch with what’s important.

Not that it’s entirely our fault, oftentimes a usability expert is just something not all developers have at their disposal. Having a key individual who has a strong grasp of the end user requirements is often your best source for usability.

Creating an easy to use application is a challenging task. Usability is a sum of all its parts, meaning an application must flow together and be logical on each page, as well as together as a whole. In this tutorial we’ll take one small piece of usability and implement it in such a way that it can even affect other pages.

The premise is quite simple, a lot of search pages, list pages or reports pages require several parameters as criteria, our goal is to cache these criteria so that the user can leave the page, return to the search page and have the criteria from the previous search pre-filled, and possibly re-execute the search automatically.

Entering information into forms is probably the most time consuming aspect of the end-users job, and probably the least considered from a developer, so this criteria caching pattern can really save your end users a lot of time.

We’ll implement a simple sample application in ASP.NET 1.1 with a search form, connected to a live database for demonstration purposes. The user can search, view the results, then navigate away from the page, and later return with the previous search fields pre-filled, all in a pattern which will keep the session clean and easy to read.

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How to Run MS Access Queries from ASP.NET – Part 2

Welcome to part 2 of this tutorial on how to execute queries requiring parameters from Microsoft Access. As previously mentioned in part 1, Microsoft Access is probably one of the most popular small scale application databases in use today, and is therefore the topic of discussion amongst many developers.

One of the surprising aspects of Visual Studio.NET 02/03 is that it did not come with an easy way to integrate Microsoft Access queries. With full support of SQL stored procedures the data wizards in Visual Studio.NET made it a breeze to program create/update/view/delete functionality automatically and will even create the required stored procedures for you.

Hence the purpose of this tutorial is 2-fold: 1 is to demonstrate how to connect to a MS Access database and execute queries which require parameters, and 2 is to implement this functionality in a scalable 3-tier design using class separation.

In part 1 of this tutorial we covered the database creation, setting up the ASP.NET project, connecting to the Access database, how to create the 3 tier application, and how to execute an MS Access query to return a set of data. This query did not require a parameter however.

During part 2 of this tutorial we will expand on our demonstration application by creating a create and update query, both of which require parameters. We will create an interface in order to visually see the create and update process on a WebForm.

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How to Run MS Access Queries from ASP.NET – Part 1

With ASP.NET version 1.1 it’s a little surprising Microsoft didn’t make working with Access databases a little easier. Visual Studio .NET 2003 and prior were mainly geared towards SQL server integration. Though you can connect to Access databases without issue, you cannot have the Data Access wizards run or create queries within Access for you like it can with stored procedures for SQL server.

The purpose of this tutorial is to achieve exactly that, to be able to connect to an Access database and execute its queries, without the use of the GUI Data wizards. We’ll take this framework and build a simple mini-application with several features over the course of this 2 part series.

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Entity Descriptor Pattern in .NET

When developing applications of a more complex nature your role as an architect or senior developer is to create reusable patterns that your development team can implement and follow. Even if the application is not an enterprise level piece of software, having clean patterns in place make your development and code implementation much smoother and easier to follow.

The reason for these patterns is very important: Each developer will of course have their own way of implementing certain things; it’s the nature of a human being to do things the best way they see fit. While each developer may have a perfectly acceptable method of implementation the fact remains that they will all be individually different, and that can create confusion in the code.

As the architect your job is to ensure the development team sticks within certain boundaries of coding and the way to achieve that is through patterns. The key to adoption within the team is to brainstorm and discuss certain implementation strategies. Then a decision is made based on the collective ideas from the team and a pattern is created that all developers will then follow.

The pattern itself shouldn’t be considered as the ultimate way to implement certain chunks of code but rather be perceived as a best effort and most importantly a uniform way of defining code segments.

That being said the purpose of this tutorial is to take a common pattern found in almost any application and define it in a simple and reusable fashion using Object Oriented (OO) techniques. The pattern we will look at relates directly to database modelling and representing single entities of information once they have been extracted from a data store.

The goal is to map an object to a database record and use OO techniques to make a developers life easier when working with these objects. For this tutorial we will use ASP.NET to implement an example application although the code and pattern can be applied to any .NET project type.

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