If I use a FileStream to create a StreamReader, will the StreamReader close when I close the FileStream or will I need to close the StreamReader too?
public void ReadFile()
{
var file = new FileStream("c:\file.txt", FileMode.Open, FileAccess.Read);
var reader = new StreamReader(file);
try
{
txtFile.Text = reader.ReadToEnd();
}
catch (Exception)
{
throw;
}
finally
{
file.Close();
}
}
Essentially yes. You don't actually have to close a StreamReader. If you do, all it does is closes the underlying stream.
@Bruno makes a good point about closing the outer-most wrapper. It is good practice to close the outer-most stream and let it close underlying streams in order to ensure all resources are released properly.
From Reflector...
public class StreamReader : TextReader
{
public override void Close()
{
this.Dispose(true);
}
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;
this.encoding = null;
this.decoder = null;
this.byteBuffer = null;
this.charBuffer = null;
this.charPos = 0;
this.charLen = 0;
base.Dispose(disposing);
}
}
}
}