How can I dispose/release a string file in this case?
<p>Im trying to use using but getting error on the using it self.</p>

<pre><code>public void Save(string path , bool Locked , PictureBox pb)
        {
            string fn;
            string t = Path.GetFileNameWithoutExtension(wo_name);
            if (File.Exists(path + "\\" + "DATABASE" + "\\" + t + "\\" + wo_name))
            {
                using  (string f = Path.Combine(path + "\\" + "DATABASE" + "\\" + t + "\\" + wo_name))
                {
                    File.Delete(f);
                }


                fn = path + "\\" + "DATABASE" + "\\" + t + "\\" + wo_name;
            }
            else
            {
                fn = path + "\\" + "DATABASE" + "\\" + wo_name + "\\" + wo_name + ".txt";
            }
            OptionsFile setting_file = new OptionsFile(fn);
            setting_file.SetKey("File Name", fn);
            setting_file.SetKey("Version", version);
            setting_file.SetKey("Button Lock", Locked.ToString());

            setting_file.SetKey("picturebox.Width", pb.Width.ToString());
            setting_file.SetKey("picturebox.Height", pb.Height.ToString());
                setting_file.SetListFloatKey("Coordinates_X", woc.Point_X);
                setting_file.SetListFloatKey("Coordinates_Y", woc.Point_Y);

                setting_file.SetListIntKey("ConnectionStart", connectionStart);
                setting_file.SetListIntKey("ConnectionEnd", connectionEnd);


        }
</code></pre>

<p>In this save function above i did:</p>

<pre><code>using  (string f = Path.Combine(path + "\\" + "DATABASE" + "\\" + t + "\\" + wo_name))
                    {
                        File.Delete(f);
                    }
</code></pre>

<p>Before it there was just string f = ....Path.... and the Fiel.Delete
I just added the using but on the using im getting error: 'string': type used in a using statement must be implicitly convertible to 'System.IDisposable'</p>
