c# copy file from textbox to selected directory

Question

I'm working with c# on wpf and running into a problem where I select some files and their filenames go into my my 'filespicked' textbox. I then have a button that is supposed to copy the files, the same ones that were selected in the textbox, to another folder. This button opens up a folder browser dialog and I select the folder I want to copy to.

The problem is that when I select the folder and click ok, I get an exception caught by my try/catch exception handler and it does not copy.

Here is my code.

private void Button_Click(object sender, RoutedEventArgs e)

    {
        FolderBrowserDialog dialog = new FolderBrowserDialog();
        dialog.Description = "Select a folder to copy to";
        dialog.ShowNewFolderButton = true;

        if (dialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
        {

            string[] files = filePickedTextBox.Text.Split('\n');

            foreach (var file in files)
            {
                // Detect and handle the event of a non-valid filename
                try
                {
                    File.Copy(file, dialog.SelectedPath);
                }
                catch (Exception ex)
                {
                    outputTextBox.Text = ex.ToString();
                    return;
                }
            }
        }

And here is the error:

System.IO.IOException: The target file "C:\Users\tj\Desktop\copied_files" is a directory, not a file. at System.IO.File.InternalCopy(String sourceFileName, String destFileName, Boolean overwrite, Boolean checkHost) at System.IO.File.Copy(String sourceFileName, String destFileName) at WpfApp1.MainWindow.Button_Click(Object sender, RoutedEventArgs e)

The error makes no sense to me because the string in the file variable is the target file, not the copied_files folder. That is the destination folder.

Answer 1

The copy destination needs to be a file, not a directory (Hence "The target file ..."). Use Path.Combine to tack the file name onto dialog.SelectedPath if you want to keep the same file name:

foreach (var file in files)
{
    // Detect and handle the event of a non-valid filename
    try
    {
        File.Copy(file, Path.Combine(dialog.SelectedPath, Path.GetFileName(file)));
    }
    catch (Exception ex)
    {
        outputTextBox.Text = ex.ToString();
        return;
    }
}