Check out example codes for "c# file directory selection". It will help you in understanding the concepts better.

Code Example 1

CommonOpenFileDialog dialog = new CommonOpenFileDialog();
dialog.InitialDirectory = "C:\\Users";
dialog.IsFolderPicker = true;
if (dialog.ShowDialog() == CommonFileDialogResult.Ok)
{
    MessageBox.Show("You selected: " + dialog.FileName);
}

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