private void ShowEditForm(object sender, EventArgs e)
        {
            var bookBorrowEdit = new BookBorrowEditForm(_bookBorrow.BookBorrowId.ToString());

            bookBorrowEdit.ShowDialog();
            Close();
        }
 private void ShowBookBorrowEditForm(object sender, EventArgs e)
 {
     if (bookBorrowsListBox.SelectedIndex == -1)
     {
         MessageBox.Show("Odaberi posudbu!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
     }
     else
     {
         var bookBorrowEdit =
             new BookBorrowEditForm(bookBorrowsListBox.SelectedItem.ToString().Substring(0, 3).OnlyNumbers());
         bookBorrowEdit.ShowDialog();
         FillBookBorrowDetails();
     }
 }