Does .Disposing a StreamWriter close the underlying stream ?

Question

The StreamWriter.Close() says it also closes the underlying stream of the StreamWriter. What about StreamWriter.Dispose ? Does Dispose also dispose and/or close the underlying stream

Answer 1

Close and Dispose are synonymous for StreamWriter.

Answer 2

StreamWriter.Close() just calls StreamWriter.Dispose() under the bonnet, so they do exactly the same thing. StreamWriter.Dispose() does close the underlying stream.

Reflector is your friend for questions like this :)

Answer 3

From StreamWriter.Close()

public override void Close()
{
    this.Dispose(true);
    GC.SuppressFinalize(this);
}

From TextWriter.Dispose() (which StreamWriter inherits)

public void Dispose()
{
    this.Dispose(true);
    GC.SuppressFinalize(this);
}

They are thus, identical.

Answer 4

To quote from Framework Design Guidelines by Cwalina and Abrams in the section about the dispose pattern:

CONSIDER providing method Close(), in addition to the Dispose(), if close is standard terminology in the area.

Apparently Microsoft follow their own guidelines, and assuming this is almost always a safe bet for the .NET base class library.