C# close stream and delete file if something failed

Question

I'm working with a file stream in C#. It's a storage cache, so if something goes bad writing the file (corrupted data, ...), I need to delete the file and rethrow the exception to report the problem. I'm thinking on how to implement it in the best way. My first attempt was:

Stream fileStream = null;
try
{
    fileStream = new FileStream(GetStorageFile(),
        FileMode.Create, FileAccess.Write, FileShare.Write);
    //write the file ...
}
catch (Exception ex)
{
    //Close the stream first
    if (fileStream != null)
    {
      fileStream.Close();
    }
    //Delete the file
    File.Delete(GetStorageFile());
    //Re-throw exception
    throw;
}
finally
{
    //Close stream for the normal case
    if (fileStream != null)
    {
      fileStream.Close();
    }
}

As you will see, if something goes bad writing the file, the fileStream will be closed twice. I know that it works, but I don't think that is the best implementation.

I think that I could remove the finally block, and close the stream in the try block, but I have posted this here because you guys are experts and I want to hear the voice of an expert.

Answer 1

If you put the fileStream in a using block you don't need to worry about closing it, and then just leave the cleaning up (deleting of the file in the catch block.

try 
{ 
    using (FileStream fileStream = new FileStream(GetStorageFile(), 
        FileMode.Create, FileAccess.Write, FileShare.Write))
    {
        //write the file ... 
    }
} 
catch (Exception ex) 
{ 
    File.Delete(GetStorageFile()); 
    //Re-throw exception 
    throw; 
}