Question

我有一个链接到SQL数据库的DropDownList。它目前显示CardCode列表。我试图这样做，以便一旦选择了CardCode，就会自动填充多个文本框（例如CardNum，CntctPerson，ListNum等）。我能够自动填充＆＃34; CardCode＆＃34;和CardNum文本框一样，值是选中但显示数据库中的第一行，我想向CardCode显示相关行，我不知道如何填充与所选CardCode相关的其他行。如何我可以这样做吗？在此先感谢

这是我的aspx.cs代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;


namespace StackOver
{
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                LoadOptions();
            }
        }
        protected void LoadOptions()
        {
            DataTable CardCode = new DataTable();

            SqlConnection connection = new SqlConnection(my connection here);
            using (connection)
            {
                SqlDataAdapter adapter = new SqlDataAdapter("SELECT CardCode, CardName, Address, CntctPrsn FROM OCRD", connection);

                adapter.Fill(CardCode);
               // DropDownList1.DataSource = customers;
                DropDownList1.DataTextField = "CardName";
                DropDownList1.DataValueField = "CardName";
                DropDownList1.DataBind();
            }
        }

       protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
        {
            string selected = DropDownList1.SelectedItem.Value;

            SqlConnection connection = new SqlConnection(my conection here);
            using (connection)
            {
                SqlCommand theCommand = new SqlCommand("SELECT CardCode, CardName, Address, CntctPrsn FROM OCRD", connection);
                connection.Open();
                theCommand.Parameters.AddWithValue("@CardCode", selected);
                theCommand.CommandType = CommandType.Text;

                SqlDataReader theReader = theCommand.ExecuteReader();

                   if (theReader.Read())
                    {
                        // Get the first row
                      // theReader.Read();

                        // Set the text box values
                        this.TextBox1.Text = theReader.GetString(0);
                        this.TextBox2.Text = theReader.GetString(1);
                        this.TextBox3.Text = theReader.GetString(2);
                        // this.TextBox4.Text = theReader.GetString(3);
                        //  TextBox5.Text = theReader.GetString(4);
                        //  TextBox6.Text = theReader.GetString(5);
                        //  TextBox7.Text = theReader.GetString(6);

                    }
                    connection.Close();
                }

            }


        }

}

这也是我的.aspx代码

<%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true"
    CodeBehind="Default.aspx.cs" Inherits="StackOver._Default" %>

<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">
</asp:Content>
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
    <h2>
        Welcome to ASP.NET!
        <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" 
            DataSourceID="SqlDataSource1" DataTextField="CardCode" 
            DataValueField="CardCode" 
            onselectedindexchanged="DropDownList1_SelectedIndexChanged">
        </asp:DropDownList>
        <asp:SqlDataSource ID="SqlDataSource1" runat="server" 
            ConnectionString="<%$ ConnectionStrings:myconnection string here %>" 
            SelectCommand="SELECT [CardCode], [CardName], [Address], [CntctPrsn] FROM [OCRD]">
        </asp:SqlDataSource>
    </h2>
    <p>
        <asp:TextBox ID="TextBox1" runat="server" ></asp:TextBox>
    </p>
    <p>
        <asp:TextBox ID="TextBox2" runat="server" ></asp:TextBox>
    </p>
    <p>
        <asp:TextBox ID="TextBox3" runat="server" ></asp:TextBox>
    </p>

    <p>
        <asp:TextBox ID="TextBox4" runat="server"></asp:TextBox>
    </p>

</asp:Content>

Answer 1

将代码中的代码替换为代码：

DropDownList1.DataValueField = "CardCode";

SqlCommand theCommand = new SqlCommand("SELECT CardCode, CardName, Address, CntctPrsn FROM OCRD where CardCode=@CardCode ", connection);

你是使用代码隐藏和数据源双方下载绑定下载所以删除Sql数据源如下所示：

<%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true"
CodeBehind="Default.aspx.cs" Inherits="StackOver._Default" %>

<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">
</asp:Content>
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
<h2>
    Welcome to ASP.NET!
    <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" 
        onselectedindexchanged="DropDownList1_SelectedIndexChanged">
    </asp:DropDownList>

</h2>
<p>
    <asp:TextBox ID="TextBox1" runat="server" ></asp:TextBox>
</p>
<p>
    <asp:TextBox ID="TextBox2" runat="server" ></asp:TextBox>
</p>
<p>
    <asp:TextBox ID="TextBox3" runat="server" ></asp:TextBox>
</p>

<p>
    <asp:TextBox ID="TextBox4" runat="server"></asp:TextBox>
</p>

Answer 2

首先，您还需要在下拉列表中存储卡片代码，而不仅仅是卡片名称

DropDownList1.DataValueField = "CardCode";

然后，在填充文本框时，您没有指定WHERE过滤器。试试这个：

SqlCommand theCommand = new SqlCommand("SELECT CardCode, CardName, Address, CntctPrsn FROM OCRD WHERE CardCode = @CardCode", connection);

从ASP.NET

2 个答案: