gridview radiobuttonlist问题 字符串格式不正确

Question

  绑定ridobuttonlist没有问题
  protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
       if (e.Row.RowType == DataControlRowType.DataRow)
        {
            int s =Convert.ToInt32(e.Row.Cells[0].Text);
            qlConnection conn = Class1.DBCon();
            conn.Open();
            string com = string.Format("select * from [Survey_Option] where [QuestionId]={0}", s);
            SqlDataAdapter da = new SqlDataAdapter(com, conn);
            DataSet ds = new DataSet();
            da.Fill(ds);
            DataTable dt = ds.Tables[0];
            conn.Close()；            RadioButtonList rb1 = (RadioButtonList)e.Row.Cells[1].FindControl("RadioButtonList1");
            rb1.DataSource = dt;
            rb1.DataTextField = "OptionName";
            rb1.DataValueField = "OptionId";
            rb1.DataBind();        }
    }
 protected void Button1_Click1(object sender, EventArgs e)
    {
        RadioButtonList rb1;        for (int i = 0; i < GridView1.Rows.Count; i++)
        {
            rb1 = GridView1.Rows[i].FindControl("RadioButtonList1") as RadioButtonList;
            SqlConnection con = Class1.DBCon();
            con.Open();
            int  optionid =Convert.ToInt32(rb1.SelectedValue ;//出现问题，字符串格式不正确。             string sql1 = string.Format("insert into [Survey_Vote](OptionId) values('{0}')", optionid);
            SqlCommand com1 = new SqlCommand(sql1, con);
             com1.ExecuteNonQuery();
        }
    }
 补充一点 rb1 = （RadioButtonList）GridView1.Rows[i].FindControl("RadioButtonList1")也会出现上述问题 ;
不求原因，只希望能给出正确的代码

Answer 1

foreach (GridViewRow gvr in GridView1.Rows)
{
    string strid= ((RadioButtonList)gvr.FindControl("RadioButtonList1")).SelectedValue;
}
试试

Answer 2

少了一个括号int  optionid =Convert.ToInt32(rb1.SelectedValue);

Answer 3

rb1.SelectedValue 的值是什么类型的？能够转换成整形吗？ 还有就是2楼说的缺了个右括号。