根据下拉选择将ID保存到数据库

我使用以下代码将BusinessID绑定为ddlIndustry下拉列表的DataValueField。 我想要做的是将选定的ID保存到不同的表（公司）。 我用ddlIndustry.SelectedValue做这个。 由于某种原因，第一个值始终保存（1），而不是选定的值。 你有什么想法可能会发生这种情况吗？

protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) BindCountry(); BindIndustry(); } private void BindCountry() { XmlDocument doc = new XmlDocument(); doc.Load(Server.MapPath("countries.xml")); foreach (XmlNode node in doc.SelectNodes("//country")) { ddlCountry.Items.Add(new ListItem(node.InnerText, node.Attributes["code"].InnerText)); ddlCountry.SelectedIndex = 94; } } private void BindIndustry() { SqlCommand cmd = null; SqlConnection conn = new SqlConnection(GetConnectionString()); conn.Open(); cmd = new SqlCommand("Select Industry, BusinessID FROM BusinessType", conn); cmd.CommandType = CommandType.Text; SqlDataAdapter da = new SqlDataAdapter(cmd); DataSet ds = new DataSet(); da.Fill(ds); conn.Close(); ddlIndustry.DataSource = ds; ddlIndustry.DataTextField = "Industry"; ddlIndustry.DataValueField = "BusinessID"; ddlIndustry.DataBind(); //ddlIndustry.Items.Insert(0, new System.Web.UI.WebControls.ListItem("-- Please Select Industry --", "0")); } private void ExecuteCompanyDetailsInsert() { SqlConnection conn = new SqlConnection(GetConnectionString()); string sql = "INSERT INTO Company (BusinessID, CompanyName, Email, AddressLine1, AddressLine2, Location, Telephone) VALUES " + " (@BusinessID, @CompanyName, @Email, @AddressLine1, @AddressLine2, @Location, @Telephone)"; try { conn.Open(); SqlCommand cmd = new SqlCommand(sql, conn); SqlParameter[] param = new SqlParameter[7]; param[0] = new SqlParameter("@BusinessID", SqlDbType.Int); param[1] = new SqlParameter("@CompanyName", SqlDbType.VarChar, 50); param[2] = new SqlParameter("@Email", SqlDbType.VarChar, 50); param[3] = new SqlParameter("@AddressLine1", SqlDbType.VarChar, 50); param[4] = new SqlParameter("@AddressLine2", SqlDbType.VarChar, 50); param[5] = new SqlParameter("@Location", SqlDbType.VarChar, 50); param[6] = new SqlParameter("@Telephone", SqlDbType.VarChar, 50); param[0].Value = ddlIndustry.SelectedValue; param[1].Value = company_name.Text; param[2].Value = company_email.Text; param[3].Value = address_line_1.Text; param[4].Value = address_line_2.Text; param[5].Value = ddlCountry.SelectedItem.Text; param[6].Value = telephone.Text; for (int i = 0; i < param.Length; i++) { cmd.Parameters.Add(param[i]); } cmd.CommandType = CommandType.Text; cmd.ExecuteNonQuery(); } catch (System.Data.SqlClient.SqlException ex) { string msg = "Insert Error:"; msg += ex.Message; throw new Exception(msg); } finally { conn.Close(); } } 

Answer 1

首先修改此代码，因为当您的页面回发到服务器时，您的industry dropdown再次绑定并且您selected value lost

 if (!Page.IsPostBack) { BindCountry(); BindIndustry(); } 

然后你就可以得到选定的价值

 ddlIndustry.SelectedValue