使用类在asp.net中从数据库填充下拉列表的方法是什么？
我试图通过使用类来填充sql server中的下拉列表，如下所示。 在将数据绑定到下拉列表时，代码会崩溃。 它给dropdownlist提供了dataValueField和datatTextField的错误。
HTML … a.aspx
C＃… a.aspx.cs
protected void Page_Load(object sender, EventArgs e) { Classes.Nationality PossibleNationality = new Classes.Nationality(); if (!Page.IsPostBack) { DataTable dataTable = PossibleNationality.getNationality(); NationalityDropDownList.DataSource = dataTable; NationalityDropDownList.DataValueField = "ID"; NationalityDropDownList.DataTextField = "Nationality"; NationalityDropDownList.DataBind(); } }
Nationality.cs
public class Nationality { public DataTable getNationality() { SqlConnection conn; SqlCommand comm; string connectionString = ConfigurationManager.ConnectionStrings["InformationConnection"].ConnectionString; conn = new SqlConnection(connectionString); comm = new SqlCommand("spGetAllUsers", conn); comm.CommandType = CommandType.StoredProcedure; DataTable dataTable; try { conn.Open(); SqlDataAdapter da = new SqlDataAdapter(); da.SelectCommand = comm; dataTable = new DataTable(); da.Fill(dataTable); } finally { conn.Close(); } return dataTable; } }
SQL程序….
ALTER PROCEDURE [dbo].[spGetNationalities] AS BEGIN select * from Nationality; END
你的getNationality方法中的这行代码……
comm = new SqlCommand("spGetAllUsers", conn);
……应该是这样的
comm = new SqlCommand("spGetNationalities", conn);
如果您的Nationality表具有列ID和国籍，则数据绑定应该有效
if (!Page.IsPostBack) { try { using (SqlConnection con = new SqlConnection("Data Source = NIPOON; Initial Catalog = CustomerOrders; Integrated Security = true")) { SqlCommand cmd = new SqlCommand("SELECT Name FROM Customer", con); con.Open(); dropDownList.DataSource = cmd.ExecuteReader(); dropDownList.DataTextField = "Name"; dropDownList.DataValueField = "Name"; dropDownList.DataBind(); } } catch (Exception Ex) { Console.WriteLine("Error: " + Ex.Message); } GetData(); }