Question

I am trying to write text to my txt file. After the first write the application crash with error

Cannot write to a closed TextWriter

My list contains links that the browser opens and I want to save all of them in txt file (like a log).

My code:

FileStream fs = new FileStream(
                    "c:\\linksLog.txt", FileMode.Append, FileAccess.Write);
StreamWriter sw = new StreamWriter(fs);

for (int i = 0; i < linksList.Count; i++)
{
    try
    {
        System.Diagnostics.Process.Start(browserType, linksList[i]);
    }
    catch (Exception) { }

    using (sw)
    {
        sw.WriteLine(linksList[i]);
        sw.Close();
    }

    Thread.Sleep((int)delayTime);

    if (!cbNewtab.Checked)
    {
        try
        {
            foreach (Process process in Process.GetProcesses())
            {
                if (process.ProcessName == getProcesses)
                {
                    process.Kill();
                }
            }
        }
        catch (Exception) { }
    }
}

Answer 1

You’re in a for loop, but you close and dispose of your StreamWriter on the first iteration:

using (sw)
{
    sw.WriteLine(linksList[i]);
    sw.Close();
}

Instead, remove that block, and wrap everything in one using block:

using (var sw = new StreamWriter(@"C:\linksLog.txt", true)) {
    foreach (var link in linksList) {
        try {
            Process.Start(browserType, list);                        
        } catch (Exception) {}

        sw.WriteLine(link);

        Thread.Sleep((int)delayTime);

        if (!cbNewtab.Checked) {
            var processes = Process.GetProcessesByName(getProcesses);

            foreach (var process in processes) {
                try {
                    process.Kill();
                } catch (Exception) {}
            }
        }
    }
}