Question

我试图动态地将数据检索到标签中。这意味着标签将随着我更改DropDownList所选项而改变。有可能吗？

ASPX：

<asp:DropDownList ID="ddl_CNo" AutoPostBack="true" runat="server" Height="16px" Width="138px" OnSelectedIndexChanged="ddl_CNo_SelectedIndexChanged" >
                </asp:DropDownList>

aspx.cs：

//page load box retrieve
    SqlConnection myConnect2 = new SqlConnection(_connStr);
    string strCommandText2 = "SELECT Card_Type, Card_Type2, Card_Number, Card_Number2, Name_On_Card, Name_On_Card2, Expired_Date, Expired_Date2 From Card_Details where Card_Id = @Card_Id";
    myConnect2.Open();
    SqlCommand cmd2 = new SqlCommand(strCommandText2, myConnect2);
    cmd2.Parameters.AddWithValue("@Card_Id", 1);

    ////open connection and retrieve data by calling ExecuteReader

    SqlDataReader dr2 = cmd2.ExecuteReader();

    if (dr2.Read())
    {

        string CNo1 = dr2["Card_Number"].ToString();
        string CNo2 = dr2["Card_Number2"].ToString();

        CNo = new List<string>();
        CNo.Add(dr2["Card_Number"].ToString());
        CNo.Add(dr2["Card_Number2"].ToString());

        ddl_CNo.DataSource = CNo;
        ddl_CNo.DataBind();

  ddl_CNo.Text = dr2["Card_Number"].ToString();
  ddl_CNo.Text = dr2["Card_Number2"].ToString();
  Lbl_CardName.Text = dr2["Name_On_Card"].ToString();
  Lbl_CardName.Text = dr2["Name_On_Card2"].ToString();
  Lbl_CardType.Text = dr2["Card_Type"].ToString();
  Lbl_CardType.Text = dr2["Card_Type2"].ToString();
  Lbl_EDate.Text = dr2["Expired_Date"].ToString();
  Lbl_EDate.Text = dr2["Expired_Date2"].ToString();


    }
    dr2.Dispose();
    dr2.Close();

    myConnect2.Close();

    if (!IsPostBack)
    {

        LoadCart();

    }
}

DDLSelectedIndexChanged：

 protected void ddl_CNo_SelectedIndexChanged(object sender, EventArgs e)
{
    {
        SqlConnection myConnect2 = new SqlConnection(_connStr);
        string strCommandText2 = "SELECT Card_Type, Card_Type2, Card_Number, Card_Number2, Name_On_Card, Name_On_Card2, Expired_Date, Expired_Date2 From Card_Details where Card_Id = @Card_Id";
        myConnect2.Open();
        SqlCommand cmd2 = new SqlCommand(strCommandText2, myConnect2);
        cmd2.Parameters.AddWithValue("@Card_Id", 1);
        SqlDataReader dr2 = cmd2.ExecuteReader();

        if (dr2.Read())
        {

            string CNo1 = dr2["Card_Number"].ToString();
            string CNo2 = dr2["Card_Number2"].ToString();

            CNo = new List<string>();
            CNo.Add(dr2["Card_Number"].ToString());
            CNo.Add(dr2["Card_Number2"].ToString());

            ddl_CNo.DataSource = CNo;
            ddl_CNo.DataBind();

            if (ddl_CNo.SelectedItem.Equals("Card_Number"))
            {
                Lbl_CardName.Text = dr2["Name_On_Card"].ToString();
                Lbl_CardType.Text = dr2["Card_Type"].ToString();
                Lbl_EDate.Text = dr2["Expired_Date"].ToString();
            }
            else if (ddl_CNo.SelectedItem.Equals("Card_Number2"))
            {
                Lbl_CardName.Text = dr2["Name_On_Card2"].ToString();
               Lbl_CardType.Text = dr2["Card_Type2"].ToString();
               Lbl_EDate.Text = dr2["Expired_Date2"].ToString();
            }
            dr2.Dispose();
            dr2.Close();

            myConnect2.Close();
        }
    }
}

参考图片：

我对所有这些都很陌生，非常感谢任何帮助：）

Answer 1

在考虑了您的场景后，我认为这将是可行的解决方案。将您的DropDownList绑定到内部页面加载然后onselctedIndexChanged我们可以在选择的CardID的基础上获取数据并绑定所有需要数据的标签。您可以根据您的规范优化代码。试试一次：

1 -- 1 == 2

使用DropDownList将数据库信息动态检索到标签中

1 个答案: