怎么取的gridview中i行的值

如何取的gridview中i行的值
gridview模版列添加按钮

protected   void   GridView1_RowCommand(object   sender,   GridViewCommandEventArgs   e)
        {
                if   (e.CommandName   ==   "aa ")
                {string   a=GridView1.Rows[i].cell[0]   }

如何得到i的值，无法用[e.RowIndex]取得行

[解决办法]

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
for (int i = 0; i < GridView1.Rows.Count; i++)
{
string a= GridView1.Rows[i].Cells[2].Text;
}

}

[解决办法]
DataRowView row = gvSomething.Rows[i].DataItem as DataRowView;
string s = row[ "Columnname "].ToString();