Setup default value if is datetimepicker in sql column null

Question

Setup default value if is datetimepicker in sql column null

 

Exp

vrijemeodjaveDateTimePicker.Value = Convert.ToDateTime(string.IsNullOrWhiteSpace(vrijemeodjaveDateTimePicker.Text) ? emptydate : prijava_radnikaDataGridView.SelectedRows[0].Cells["dataGridViewTextBoxColumn3"].Value);

Default value

private DateTime emptydate = DateTime.Parse("2018-01-01 00:00:00");