.NET Tip: Managing Resources with the Using Statement

Last week, I showed you how you can help ensure that your objects release their resources by implementing IDisposable. This week, I want to show you the using statement that allows you to specify when your objects release their resources. Objects declared in the using statement will explicitly be disposed when the end of the using block is reached. I often use nested using statements for data access to precisely control the creation and disposal of my objects. Here is how you can take advantage of the using statement to create a database connection, create a command, and execute a data reader to access your data.

using (SqlConnection CN =
   new SqlConnection("*** Your connection string here ***"))
{
   CN.Open();
   using (SqlCommand cmd =
          new SqlCommand("SELECT * FROM authors", CN))
   {
      using (SqlDataReader dr = cmd.ExecuteReader())
      {
         // Access elements items here
      }
   }
}

By nesting the using statements above, you can be sure you are creating objects only when necessary and that, once everything is finished, your objects will all be disposed of in a timely manner. If an error should occur anywhere along the way, any objects created up to that point will still be disposed of when the using block is exited. The only caveat is that the object declared in the using statement must implement the IDisposable interface. Keep this in mind if you plan on taking advantage of the using statement with your own classes.

About the Author

Jay Miller is a Software Engineer with Electronic Tracking Systems, a company dedicated to robbery prevention, apprehension, and recovery based in Carrollton, Texas. Jay has been working with .NET since the release of the first beta and is co-author of Learn Microsoft Visual Basic.NET In a Weekend. Jay can be reached via email at jmiller@sm-ets.com.



Comments

  • There are no comments yet. Be the first to comment!

Leave a Comment
  • Your email address will not be published. All fields are required.

Top White Papers and Webcasts

  • Live Event Date: May 7, 2014 @ 1:00 p.m. ET / 10:00 a.m. PT This eSeminar will explore three popular games engines and how they empower developers to create exciting, graphically rich, and high-performance games for Android® on Intel® Architecture. Join us for a deep dive as experts describe the features, tools, and common challenges using Marmalade, App Game Kit, and Havok game engines, as well as a discussion of the pros and cons of each engine and how they fit into your development …

  • Download the Information Governance Survey Benchmark Report to gain insights that can help you further establish business value in your Records and Information Management (RIM) program and across your entire organization. Discover how your peers in the industry are dealing with this evolving information lifecycle management environment and uncover key insights such as: 87% of organizations surveyed have a RIM program in place 8% measure compliance 64% cannot get employees to "let go" of information for …

Most Popular Programming Stories

More for Developers

Latest Developer Headlines

RSS Feeds