Any best practices on whether to access class instance members directly or pass state as parameters to a class method?
<p>For example:</p>

<pre><code>Foo
{
     private int _instanceData;

    // Do this?
    private void Bar1(int instanceData) { // some work using 'instanceData' }

    // Or this?
    private void Bar1( ) { // some work using '_instanceData' }
}
</code></pre>
