C# 求gridview与RowDataCount之和

好的，我有4列名为actual，4列名为target，我需要对所有实际列求和，并将总数传递给一个标签。。。有人能帮忙吗

到目前为止，我所知道的是不正确的

public void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
        {

            if (e.Row.RowType == DataControlRowType.DataRow) //checking the index of cells and changing the font colour
            {

                System.Data.DataRowView drv = (System.Data.DataRowView) e.Row.DataItem;
                DataTable dt = drv.Row.Table;

                for (int i = 0; i < e.Row.Cells.Count; i++)
                {
                    if (dt.Columns[i].ColumnName.Contains("Actual"))
                    {
                        e.Row.Cells[i].ForeColor = Color.Red;
                    }


                    dt.Columns.Add("Total", typeof(Double));

                    foreach (DataRow row in dt.Rows)
                    {
                        int sum = row.Table.Columns<DataColumn>().Sum(dc => (int)row[dc]);
                        row.SetField("Total", sum);
                        labeltotal.Text = sum.ToString();
                    }

                }

public void GridView1_RowDataBound（对象发送方，GridViewRowEventArgs e）
{
if（e.Row.RowType==DataControlRowType.DataRow）//检查单元格索引并更改字体颜色
{
System.Data.DataRowView drv=（System.Data.DataRowView）e.Row.DataItem；
DataTable dt=drv.Row.Table；
for（int i=0；i（int）row[dc]）；
行设置字段（“总计”，总和）；
labeltotal.Text=sum.ToString（）；
}
}

您可以这样做

Int32 total = 0; 
protected void GridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        total = total + Convert.ToInt32(e.Row.Cells[1].Text);
        //here you can give the column no that you want to total like e.Row.Cells[1] for column 1
        lblTotal.Text = total.ToString();
    }
}