Null / Empty 값일 경우 체크하기
int i = dataGridView1.Rows.Count; for (int j = 0; j < i; j++) { string strCol2 = null; string strCol3 = null; if (dataGridView1.Rows[j].Cells[1].Value == null || dataGridView1.Rows[j].Cells[1].Value == DBNull.Value ) strCol2 = "----"; else strCol2 = dataGridView1.Rows[j].Cells[1].Value.ToString(); if (dataGridView1.Rows[j].Cells[2].Value == null || dataGridView1.Rows[j].Cells[2].Value == DBNull.Value ) strCol3 = "----"; else strCol3 = dataGridView1.Rows[j].Cells[2].Value.ToString(); }