C＃datagridview行总和if

Question

如何将datagridview值相加得文本框值= datagridview值？这是我的代码。现在不总结，但只取最后一个值。

if (row.Cells["SSCC"].Value.ToString() == txt_naujas_sscc.Text)
            {
                int sum = 0;
                //for (int i = 0; i < dataGridView1.Rows.Count; i++)
                //{
                sum = sum + int.Parse(row.Cells["QuantityDespatched"].Value.ToString());
                txt_sscc_pre_ska.Text = sum.ToString();
                //}
            }

Answer 1

int sum = 0;
for (int i = 0; i < dataGridView1.Rows.Count; ++i)
{
   if (dataGridView1.Rows[i].Cells["SSCC"].Value.ToString() == txt_naujas_sscc.Text) {
   sum += Convert.ToInt32(dataGridView1.Rows[i].Cells["QuantityDespatched].Value);
   }
}
txt_sscc_pre_ska.Text = sum.ToString();