private void TasksGV_CellContentClick(object sender, DataGridViewCellEventArgs e) { var senderGrid = (DataGridView)sender; if (senderGrid.Columns[e.ColumnIndex] is DataGridViewButtonColumn && e.RowIndex >= 0) { if (e.ColumnIndex == 4) { DataGridViewRow row = this.TasksGV.Rows[e.RowIndex]; var selectedTaskId = row.Cells[0].Value.ToString(); var detailsForm = new TaskDetailsForm(selectedTaskId); detailsForm.ShowDialog(); } } }