Schmalz - C# Database Basics

Copyright 2012 Michael Schmalz

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Using databases in C# can be daunting for developers moving from VB6, VBA, or Access. From the differences in the .NET syntax to the curly braces and semicolons, just looking at the code in C# for the first time can be intimidating. As you start to use C#, the small changes you need to make become easier and the code starts to flow nicely. However, you will likely find that many ways of working with data and databases that were easy in VB6 and VBA can be challenging when attempted for the first time in C#.

When you were programming in Classic VB, you could count on a good solid example of how to use a particular method, and it would be in context. For instance, if you were looking at a connection string example, it would likely include how to connect to the database, and it would probably also include a recordset or query. In C# and the other .NET languages, you will find fewer full examples and more examples that simply show the syntax. Or worse, theyll show the other objects in the example, but wont explain how to create those objects or explain where the object needs to be declared (at the form level or at the procedure level).

What led to this book was a challenge that I faced while doing something that I thought should have been very simple. I wanted to create a form with a datagrid that would load a table or query at runtime with the ability to filter, sort, and edit the records. I could do this task with Classic VB in a few minutes and in even less time with VBA inside of Access. With C#, there were pieces that were very simple, but only simple when building the connection to a single database and a single table that you define at design time. Getting code to change the datasource at runtime or connecting to a different table when your database schema changes was significantly more challenging. In addition, the help available online from within Visual Studio or even from an Internet search wasnt very complete. It isnt enough to know the method that you need to call; you need to understand where the variables are declared, the changes that are needed to the properties on the datagrid, the using references that are required, etc. Once you see it, the code is very clear, but it is less than straightforward when you are starting out.