GetShortPathName

I would like to make "f.FileName" and "f.SelectedPath"  below the short paths, but I'm not sure what I need to declare...I keep getting errors beyond the syntax of my GetShortPathName(xx,xxx,xx)
so I figured I'd just let someone get the points...


Here's the current code that I want to change to shortpath:

        private void buttonBrowseFiles_Click(object sender, EventArgs e)
        {
            using (OpenFileDialog f = new OpenFileDialog())
            {
                f.FileName = this.textBoxBackupSelection.Text;
                f.Multiselect = false;

                if (f.ShowDialog() == DialogResult.OK)
                {
                    this.textBoxBackupSelection.Text = f.FileName;
                }
            }
        }

        private void buttonBrowseFolders_Click(object sender, EventArgs e)
        {
            using (FolderBrowserDialog f = new FolderBrowserDialog())
            {
                f.ShowNewFolderButton = false;
                f.RootFolder = Environment.SpecialFolder.MyComputer;

                f.SelectedPath = this.textBoxBackupSelection.Text;

                if (f.ShowDialog() == DialogResult.OK)
                {
                    this.textBoxBackupSelection.Text = f.SelectedPath;
                }
            }
        }