http://msdn.microsoft.com/zh-cn/library/bb907626.aspx
再结合如下：
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
//编辑按扭
if (e.CommandName == "Edit")
{
//设置编辑行高亮显示
this.GridView1.EditRowStyle.BackColor = Color.FromName("#F7CE90");
//string index= this.GridView1.DataKeys[Convert.ToInt32(e.CommandArgument)].Value.ToString();
int index = Convert.ToInt32(e.CommandArgument);
GridViewRow row = GridView1.Rows[index];
string xh3 = row.Cells[3].Text;
}