c# streamwriter "process cannot access file" error even when it's closed and disposed

Question

I am making simple text editor and got problems with saving. So I have 2 codes for saving, one is to save file using button and another ctrl+s keyboard shortcut, when saving with button everything works perfectly, but when i save with shortcut i get this error:

"process cannot access file because it's used by another process"

here is my code for button save: `

        saveFileDialog1.FileName = currentname;

        if (saveFileDialog1.ShowDialog() == DialogResult.OK)
        {

            StreamWriter writer = new StreamWriter(saveFileDialog1.OpenFile());

            writer.WriteLine(richTextBox1.Text);

            writer.Dispose();
            writer.Close();

            //so i have tabs in my editor so user can switch between them.
            //and this is the only way i found which tab is opened now.
            for (int i = 0; i < labels.Count; i++)
            {
               //i created new class that holds some variables including "isUsed" 
               //and Label itself.
                if (labels[i].isUsed)
                {
                    labels[i].Text = Path.GetFileName(saveFileDialog1.FileName);
                    labels[i].setText(labels[i].Text);
                    labels[i].path = saveFileDialog1.FileName;
                    break;
                }
            }

        }`

script above works normally, but the script below doesn't:

        public void save(){

        bool found = false;
       //that is class i made.
        AdvancedLabel label = new AdvancedLabel();

        //I hold all tabs in "Labels" List.
        for (int i = 0; i < labels.Count; i++)
        {
           //so if loop found the tab that is opened now...
            if (labels[i].isUsed)
            {
                label = labels[i];
                found = true;
                break;
             }
        }
        if (found)
        {
            try
            {

                label.label.Text.Remove(label.label.Text.Length - 1);

                //here i always get this error.
                StreamWriter writer = new StreamWriter(label.path);

                writer.WriteLine(richTextBox1.Text);
                label.setText(label.Text.Remove(label.Text.Length - 1));
                writer.Dispose();
                writer.Close();

            }
            catch (Exception e)
            {
                status.Text = "status: " + e.Message + ". Failed to save :(";

            }
        }
    }

Here is the full error:

An unhandled exception of type 'System.IO.IOException' occurred in mscorlib.dll

Additional information: The process cannot access the file 'C:\Users\nika\Desktop\dd.html' because it is being used by another process.

EDIT:

thanks to you all guys, as i understood i should be using "using" statement and here is waht i came up with:

I forgot to mention that i am also opening file using stramreader. I changed it to "Using" statement but same things happen, even tho i am now using: File.appendalltext statement. This also works, but only if i save with button.

here is how i changed it (file opener not writers): `

          using (var sr = new StreamReader(openFileDialog1.FileName))
            {
                bool found = false;

                for (int i = 0; i < labels.Count; i++)
                {
                    if (labels[i].path == openFileDialog1.FileName)
                    {
                        found = true;

                        break;
                    }
                }
                if (!found)
                {

                    richTextBox1.Text = "";
                    richTextBox1.Text = sr.ReadToEnd();

                    spawnLabel();
                }
            }`

ps(this sounds so stupid)

as @GauravKP suggested:

any help will be appreciated! thanks!

--Nick.

Answer 1

Always use "using" when you are dealing with stream objects.

using (var stream = ...)
{
    /* code */

    stream.Close();
}

This is what documentation says:

As a rule, when you use an IDisposable object, you should declare and instantiate it in a using statement. The using statement calls the Dispose method on the object in the correct way.

The correct way is a key word here.

Because even though we call Dispose , "there is always a danger that the unmanaged resources will not be released, because the consumer of an object fails to call its Dispose method. "