FileStream.WriteLine() is not writing to file

Question

I am trying to make a simple software which stores data in a TXT log file. This is my code

FileStream fs = null;
StreamWriter fw = null;
try
{
    fs= new FileStream(Environment.GetFolderPath(Environment.SpecialFolder.Desktop)+"/textme.txt", FileMode.OpenOrCreate, FileAccess.ReadWrite);
    fw = new StreamWriter(fs);
    fw.Write("sadadasdsadsadsadas");

    for (int i = 0; i < AnimalShelter.AnimalList.Count; i++)
    {
        fw.WriteLine("<chipNr>" + AnimalShelter.AnimalList[i].ChipRegistrationNumber + "<chipNr>");
        Console.WriteLine("<chipNr>" + AnimalShelter.AnimalList[i].ChipRegistrationNumber + "<chipNr>");
    }
}
catch(IOException)
{
    MessageBox.Show("ERROR THROWN");
}
finally
{
    if (fs!= null) fs.Close();
    //  if (fw != null) fw.Close();
}

What I achieved is: the file gets created, but nothing gets written in it. I checked a lot of posts but I could not find any particular help.

Answer 1

Adding a call to Flush the stream works. This is because you are wrapping the FileStream. StreamWriter will write to the FileStream, but you need to indicate when to send the Stream to the actual file. Also, you can exchange your try finally with a using:

try
{
    using (var fs = new FileStream(Environment.GetFolderPath(Environment.SpecialFolder.Desktop)+"/textme.txt", FileMode.OpenOrCreate, FileAccess.ReadWrite))
    {
        using (var fw = new StreamWriter(fs))
        {
            fw.Write("sadadasdsadsadsadas");

            for (int i = 0; i < AnimalShelter.AnimalList.Count; i++)
            {
                fw.WriteLine("<chipNr>" + AnimalShelter.AnimalList[i].ChipRegistrationNumber + "<chipNr>");
                Console.WriteLine("<chipNr>" + AnimalShelter.AnimalList[i].ChipRegistrationNumber + "<chipNr>");

            }
            fw.Flush(); // Added
        }
    }
}
catch(IOException)
{
    MessageBox.Show("ERROR THROWN");
}