Does disposing streamreader close the stream?

c# stream streamreader
Nefzen picture Nefzen · Jun 30, 2009 · Viewed 69.6k times · Source

I am sending a stream to methods to write on, and in those methods I am using a binary reader/wrtier. When the reader/writer gets disposed, either by using or just when it is not referenced, is the stream closed as well??

I would send a BinaryReader/Writer, but I am using a StreamReader too (maybe I should go around that. I am only using that for GetLine and ReadLine). This is quite troublesome if it closes the stream each time a writer/reader gets closed.

Answer

Jon Skeet picture Jon Skeet · Jun 30, 2009

Yes, StreamReader, StreamWriter, BinaryReader and BinaryWriter all close/dispose their underlying streams when you call Dispose on them. They don't dispose of the stream if the reader/writer is just garbage collected though - you should always dispose of the reader/writer, preferrably with a using statement. (In fact, none of these classes have finalizers, nor should they have.)

Personally I prefer to have a using statement for the stream as well. You can nest using statements without braces quite neatly:

using (Stream stream = ...)
using (StreamReader reader = new StreamReader(stream, Encoding.Whatever))
{
}

Even though the using statement for the stream is somewhat redundant (unless the StreamReader constructor throws an exception) I consider it best practice as then if you get rid of the StreamReader and just use the stream directly at a later date, you'll already have the right disposal semantics.

Related questions

Reading large text files with streams in C#

I've got the lovely task of working out how to handle large files being loaded into our application's script editor (it's like VBA for our internal product for quick macros). Most files are about 300-400 KB which is fine loading. …

Read More
Should I call Close() or Dispose() for stream objects?

Classes such as Stream, StreamReader, StreamWriter etc implements IDisposable interface. That means, we can call Dispose() method on objects of these classes. They've also defined a public method called Close(). Now that confuses me, as to what should I call …

Read More
How To Use HttpWebRequest/Response To Download A Binary (.exe) File From A Web Server?

I am writing a program that needs to download an .exe file from a website and then save it to the hard drive. The .exe is stored on my site and it's url is as follows (it's not the real …

Read More