엑셀파일을 Open 선택하여 DataGridView로 읽어오기 private void btnOpen_Click(object sender, EventArgs e) { using (OpenFileDialog openFileDialog1 = new OpenFileDialog()) { openFileDialog1.Filter = "Excel File|*.xlsx;*.xls"; openFileDialog1.Title = "Import Excel"; openFileDialog1.Multiselect = false; if (openFileDialog1.ShowDialog() != DialogResult.Cancel) { string filePath = openFileDialog1.FileName; string fil..