using-keyword-blog-post

using-keyword-compiler-translated.cs

{
  StreamReader sr = new StreamReader(filename);
  try
  {
    String text = sr.ReadToEnd();
    return text;
  }
  finally
  {
    if (sr != null)
      ((IDisposable)sr).Dispose();
  }
}

using-keyword-read-file.cs

public string ReadFromFile(string filename)
{
  using (StreamReader sr = new StreamReader(filename))
  {
    String text = sr.ReadToEnd();
    return text;
  }
}

using-keyword.cs

public Product GetProductById(int productId)
{
  using (ProductContext db = new ProductContext) 
  {
     return db.Products.SingleOrDefault(p => p.Id == productId);    
  }
}