SqlConnection conn = new                        SqlConnection("server=.;database=RestOL;uid=sa;pwd=123456;");
            conn.Open();
            SqlCommand sql = new SqlCommand("select * from Dishes ", conn);
            //有6列
            SqlDataAdapter sda = new SqlDataAdapter(sql);
            DataSet ds = new DataSet();
            sda.Fill(ds);
            int n = ds.Tables[0].Rows.Count;
            for (int i = 0; i < n; i++)
            {
                
                    this.Image1.ImageUrl = ds.Tables[0].Rows[i][0].ToString();
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