C#反射获取数据库字段

static string sqlselect = "insert into {0}({1}) values ({2})";
(这个方法可以适用于任何数据库的插入语句)
        public static int managerRegister<T>(T field) {
            string fieldName = "";
            string fieldList = "";
            string fieldValue = "";
            int k = 0;
            Type tf = typeof(T);
            fieldName = tf.Name;//获取类型名称
            PropertyInfo[] pinfo = tf.GetProperties();//获取属性
            string[] paraList = new string[pinfo.Length];//参数化查询字段的数组
            List<SqlParameter> para = new List<SqlParameter>();//用于放置参数化查询
            foreach (PropertyInfo p in pinfo)
            {
                fieldList += p.Name + ",";
                fieldValue += "‘" + p.GetValue(field).ToString() + "‘" + ",";
                paraList[k] = p.Name;
                para.Add(new SqlParameter("@" + paraList[k], fieldValue));
                k = k + 1;//当循环执行时k加一使得数组能够连续获取到字段
            }
            fieldList = fieldList.Substring(0, fieldList.Length - 1);//去除最后一个逗号
            fieldValue = fieldValue.Substring(0, fieldValue.Length - 1);
            sqlselect = string.Format(sqlselect, fieldName, fieldList, fieldValue);
            int value = DBhelper.ExcuteQuery(sqlselect, para.ToArray());//调用自己写的一个数据库插入语句并返回一个值
            return value;//返回插入语句的情况
        }
以下是我的数据库字段

public static int ExcuteQuery(string sql, SqlParameter[] para) {
            int value;
            SqlCommand cmd = SqlCmd(sql);
            cmd.Parameters.AddRange(para);
            try
            {
                 value = cmd.ExecuteNonQuery();
                 return value;
            }
            catch
            {
                return -1;
            }           
        }

protected void Btn_Save_Click(object sender, EventArgs e)
        {
            Bc_Login a = new Bc_Login() { username = txt_Username.Text, pwd = txt_Repassword.Text };
            if (txt_Password.Text != "" && txt_Username.Text != "" && txt_Repassword.Text != "")
            {
                int value = ManagerRegister.managerRegister<Bc_Login>(a);
                if (value > 0)
                {
                    Response.Write("<script>alert(\"注册成功！\")</script>");
                    Response.Redirect("index.aspx");
                }
                else
                {
                    Response.Write("<script>alert(\"注册失败！请检查用户名或密码后重试！\")</script>");
                }
            }
            else {
                Response.Write("<script>alert(\"请检查用户名或密码!\")</script>");
            }
        }