Question

c#里dropdownlist和Textbox关联的问题！

我在TextBox里面输入客户的名字，查询数据库后，要求把这个客户的保单ID绑定到dropdownlist里面，然后点选dropdownlist里面的保单ID，在下面查看这张保单的所有信息。

注：同一个客户名，保单可以是多张,ID也就是多个！！！要求所有ID都绑定进去，并且按照时间排序！下面是我自己写的一部分，其余的不知道怎么写了，请帮我续写完，解决后追分50！！
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;

public partial class sptable : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void Button1_Click(object sender, EventArgs e)
{
string ConnString = "server=.;database=service;user id=sa;pwd=";
SqlConnection conn = new SqlConnection(ConnString);
SqlCommand comm = new SqlCommand();
comm.Connection = conn;
conn.Open();
if (TextBox8.Text == "")
{
Response.Write("<script>alert('客户姓名不能为空！')</script>");
}
else
{
comm.CommandText = "select * from suopei where spr = '" + TextBox8.Text + "'";
SqlDataReader sdr = comm.ExecuteReader();
if (sdr.Read())
{

DropDownList1.SelectedValue = sdr["spid"].ToString();

}
else
{
Response.Write("<script>alert('不存在该客户的信息，请核对后重新输入！')</script>");
}
sdr.Close();
conn.Close();
}
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
SqlConnection conn = new SqlConnection(ConnString);
string pid = DropDownList1.SelectedValue;
SqlCommand comm = new SqlCommand();
comm.Connection = conn;
conn.Open();
comm.CommandText = "select * from suopei where spid = " + pid;
SqlDataReader sdr = comm.ExecuteReader();
if (sdr.Read())

{
Label2.Text = sdr["djrq"].ToString();
Label9.Text = sdr["spid"].ToString();
Label11.Text = sdr["clxh"].ToString();
TextBox5.Text = sdr["spyy"].ToString();
TextBox6.Text = sdr["cljg"].ToString();
TextBox7.Text = sdr["khyj"].ToString();
Label12.Text = sdr["slr"].ToString();
}

sdr.Close();
conn.Close();

}
}

Answer 1

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;

public partial class sptable : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void Button1_Click(object sender, EventArgs e)
{
string ConnString = "server=.;database=service;user id=sa;pwd=";
SqlConnection conn = new SqlConnection(ConnString);
SqlCommand comm = new SqlCommand();
comm.Connection = conn;
conn.Open();
if (TextBox8.Text == "")
{
Response.Write("<script>alert('客户姓名不能为空！')</script>");
}
else
{
comm.CommandText = "select * from suopei where spr = '" + TextBox8.Text + "'";
SqlDataAdapter sda = new SqlDataAdapter(comm);
DataSet ds = new DataSet();
sda.Fill(ds);
if (ds.Tables[0].Rows.Count > 0)
{
this.DropDownList1.DataSource = ds;
this.DropDownList1.DataValueField = "spid";//弯孙 selectvalue
this.DropDownList1.DataTextField = "";//selecttext 对应的数据库字段，下拉框显示的值，自己确定
this.DropDownList1.DataBind();
}
else
{
Response.Write("<script>alert('不埋宏链存在该客户的信息，请核对后重新输入！')</script>"绝伍);
}
conn.Close();
}
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
SqlConnection conn = new SqlConnection(ConnString);
string pid = DropDownList1.SelectedValue;
SqlCommand comm = new SqlCommand();
comm.Connection = conn;
conn.Open();
comm.CommandText = "select * from suopei where spid = " + pid;
SqlDataReader sdr = comm.ExecuteReader();
if (sdr.Read())
{
Label2.Text = sdr["djrq"].ToString();
Label9.Text = sdr["spid"].ToString();
Label11.Text = sdr["clxh"].ToString();
TextBox5.Text = sdr["spyy"].ToString();
TextBox6.Text = sdr["cljg"].ToString();
TextBox7.Text = sdr["khyj"].ToString();
Label12.Text = sdr["slr"].ToString();
}

sdr.Close();
conn.Close();

}
}

Answer 2

DropDownList1.SelectedValue = sdr["spid"].ToString();
这里你写错了，你是要将查询出来的ID号绑定携樱返到DropDownList中去，
DropDownList1.SelectedValue这个方法肯定不行，颂培你可以这样：
DropDownList1.Items.Add(sdr["spid"].ToString());
后辩饥面的就没有错了~~

Answer 3

用户名 和 保单 是 1对多
所以
select * from tablename where 用户名 = 'x'
这个弄出来的正茄数据读取器应该是多个数据
所以应该用while（sdr.Read()）
{
DropDownList1.Items.Add(sde["字段"].ToString);
}
这个是绑定，然后当选择项改变的时候重新根据这个值禅皮搜索。因为不了解你的数据库所以不好举袭察具体说
大概就是 select * from tablename where id ='xxx'
id代表的表单应该是唯一的 读出来就可以了。

Answer 4

在TextChanged函数中执行就行啦，我做了一个textbox输入数尘高盯据回车后就可以更新DropDownlist里的数据。如果要及时显示，不回车，就用ajax就行派和啦，加个ScriptManager和UpdatePanel就可以啦。
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.OracleClient;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void TextBox1_TextChanged(object sender, EventArgs e)
{
if (TextBox1.Text != "")
{
string conn_str = "Data Source=****;user=**;password=**";
using (OracleDataAdapter oda = new OracleDataAdapter("select a.times from tb_test a where tel='123'", conn_str))
{
DataTable dt = new DataTable();
oda.Fill(dt);
for (int i = 0; i < dt.Rows.Count; i++)
{
DropDownList1.Items.Add(dt.Rows[i][0].ToString());
}
}
}
}
}
不知道是否对你有念坦用~~~~