Determining file state (open or closed)

[Nitin1981]

Hi all! I'm using following code string[] arrWords; StreamReader objSr; StreamWriter objSw; try { if (openFileDialog1.ShowDialog() == DialogResult.OK) { txtFileName.Text = openFileDialog1.FileName; objSr = new StreamReader(txtFileName.Text); string strFile = objSr.ReadToEnd(); arrWords = strFile.Split('\n'); objSr.Close(); objSw = new StreamWriter(txtFileName.Text, false); for (int i = 0; i < arrWords.Length; i++) { arrWords[i] = arrWords[i].ToLower(); objSw.WriteLine(arrWords[i]); } objSw.Close(); } } catch (Exception ex) { MessageBox.Show(ex.ToString()); } finally { if (objSr != null) { objSr.Dispose(); } if (objSw != null) { objSw.Dispose(); } } 1. Now I want to check in finally block if file is opened (due to any exception it did not get closed) and close it(like we do with a Connection object in ADO.net) over there. How can I do this? 2. Also a warning comes if I use code like this that objSr and objSw is used before it has been assigned a value how to overcome it.? Thanks

[Steve]

I would move the call to objSw.Close() into the finally block, as it will always be executed there and then you don't have to worry about any exceptions that may or may not have occured. You should do this on most occasions to make sure that the connection gets closed correctly no matter what happens. To overcome the warning, set the objects to null on declaration. This means they are explicity set to null, and you're not inferring anything.

[Nitin1981]

Thanks Steve! the second warning haunted me for a long time. Now I got at it. Regards Nitin

[S Senthil Kumar]

You could do away with the try/finally blocks and use the using statement instead.

using (StreamReader objSr = new StreamReader(...))
{
using (StreamWriter objSW = new StreamWriter(...))
{
...
}
}

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