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

A quick jump into Reflector.NET shows that the Close() method on StreamWriter is:

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

And StreamReader is:

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

The Dispose(bool disposing) override in StreamReader is:

protected override void Dispose(bool disposing)
{
    try
    {
        if ((this.Closable && disposing) && (this.stream != null))
        {
            this.stream.Close();
        }
    }
    finally
    {
        if (this.Closable && (this.stream != null))
        {
            this.stream = null;
            /* deleted for brevity */
            base.Dispose(disposing);
        }
    }
}

The StreamWriter method is similar.

So, reading the code it is clear that that you can call Close() & Dispose() on streams as often as you like and in any order. It won’t change the behaviour in any way.

So it comes down to whether or not it is more readable to use Dispose(), Close() and/or using ( ... ) { ... }.

My personal preference is that using ( ... ) { ... } should always be used when possible as it helps you to “not run with scissors”.

But, while this helps correctness, it does reduce readability. In C# we already have plethora of closing curly braces so how do we know which one actually performs the close on the stream?

So I think it is best to do this:

using (var stream = ...)
{
    /* code */

    stream.Close();
}

It doesn’t affect the behaviour of the code, but it does aid readability.

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