我在添加/编辑表单页面上有两个下拉列表控件，一个用于国家/地区（称为CountryCode），另一个用于区域/状态（称为ProvinceCode）。已设置代码，以便当用户从国家/地区下拉列表中选择“美国”时，区域下拉列表将填充所有有效的美国州。如果用户从国家/地区下拉列表中选择“加拿大”，则区域下拉列表中将填入有效省份。此功能正常，但是当选择“加拿大”时，由于某种原因，区域下拉列表的值永远不会保存到数据库中。我不确定为什么会这样，特别是因为我可以拯救美国各州。
这是用于填充国家和地区下拉列表的代码：
protected void Page_Init(object sender, EventArgs e)
{
CountryCode.DataSource = CountryDataSource.LoadAll("Name");
CountryCode.DataBind();
InitCountryAndProvince();
}
private void InitCountryAndProvince()
{
//MAKE SURE THE CORRECT ADDRESS IS SELECTED
Address address = this.Address;
bool foundCountry = false;
if (!string.IsNullOrEmpty(address.CountryCode))
{
ListItem selectedCountry = CountryCode.Items.FindByValue(address.CountryCode);
if (selectedCountry != null)
{
CountryCode.SelectedIndex = CountryCode.Items.IndexOf(selectedCountry);
foundCountry = true;
}
}
if (!foundCountry)
{
Warehouse defaultWarehouse = AbleContext.Current.Store.DefaultWarehouse;
ListItem selectedCountry = CountryCode.Items.FindByValue(defaultWarehouse.CountryCode);
if (selectedCountry != null) CountryCode.SelectedIndex = CountryCode.Items.IndexOf(selectedCountry);
}
//MAKE SURE THE PROVINCE LIST IS CORRECT FOR THE COUNTRY
UpdateCountry();
//NOW LOOK FOR THE PROVINCE TO SET
ListItem selectedProvince = ProvinceCode.Items.FindByValue(address.Province);
if (selectedProvince != null) ProvinceCode.SelectedIndex = ProvinceCode.Items.IndexOf(selectedProvince);
}
private void UpdateCountry()
{
//SEE WHETHER POSTAL CODE IS REQUIRED
string[] countries = AbleContext.Current.Store.Settings.PostalCodeCountries.Split(",".ToCharArray());
//PostalCodeRequired.Enabled = (Array.IndexOf(countries, Country.SelectedValue) > -1);
//SEE WHETHER PROVINCE LIST IS DEFINED
IList<Province> provinces = ProvinceDataSource.LoadForCountry(CountryCode.SelectedValue);
if (provinces.Count > 0)
{
IEnumerable<Province> sortedProvinces = provinces.OrderBy(f => f.Name);
provinces = sortedProvinces.ToList();
ProvinceCode.Visible = false;
ProvinceCode.Visible = true;
ProvinceCode.Items.Clear();
ProvinceCode.Items.Add(string.Empty);
foreach (Province province in provinces)
{
string provinceValue = (!string.IsNullOrEmpty(province.ProvinceCode) ? province.ProvinceCode : province.Name);
ProvinceCode.Items.Add(new ListItem(province.Name, provinceValue));
}
ListItem selectedProvince = FindSelectedProvince();
if (selectedProvince != null) selectedProvince.Selected = true;
ProvinceCode.Enabled = true;
ProvinceCode.Text = string.Empty;
}
else
{
ProvinceCode.Visible = true;
ProvinceCode.Visible = false;
ProvinceCode.Items.Clear();
//Province2Required.Enabled = false;
}
}
private ListItem FindSelectedProvince()
{
string defaultValue = ProvinceCode.Text;
if (string.IsNullOrEmpty(defaultValue)) defaultValue = Request.Form[ProvinceCode.UniqueID];
if (string.IsNullOrEmpty(defaultValue)) return null;
defaultValue = defaultValue.ToUpperInvariant();
foreach (ListItem item in ProvinceCode.Items)
{
string itemText = item.Text.ToUpperInvariant();
string itemValue = item.Value.ToUpperInvariant();
if (itemText == defaultValue || itemValue == defaultValue) return item;
}
return null;
}
protected void Country_Changed(object sender, EventArgs e)
{
//UPDATE THE FORM FOR THE NEW COUNTRY
UpdateCountry();
}
这是保存方法的一部分，其中包含国家和地区下拉列表控件：
private void SaveCustomerInfo(int CustID)
{
int currentUserID = AbleContext.Current.UserId;
string editQuery = "UPDATE Customers SET BillToRegion = @BillToRegion, BillToCountry = @BillToCountry WHERE CustomerID = @CustomerID";
string addQuery = "INSERT INTO Customers (BillToRegion, BillToCountry) VALUES(@BillToRegion, @BillToCountry)";
try
{
using (SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["AbleCommerce"].ToString()))
{
cn.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = cn;
cmd.Parameters.Add(new SqlParameter("@BillToRegion", ProvinceCode.SelectedValue));
cmd.Parameters.Add(new SqlParameter("@BillToCountry", CountryCode.SelectedValue));
cmd.ExecuteNonQuery();
cn.Close();
}
}
catch (Exception exception)
{
Logger.Warn("Admin\\People\\Customers\\EditCustomer.aspx - SaveCustomerInfo", exception);
}
这是在页面加载以使用数据库中的值填充字段时调用的代码（如果用户正在编辑现有条目）：
protected void Page_Load(object sender, EventArgs e)
{
_CustomerID = AlwaysConvert.ToInt(Request.QueryString["CustomerID"]);
int.TryParse(Request.QueryString["CustomerID"], out _CustomerID);
if (_CustomerID == 0)
{
AddBtn.Visible = true;
EditBtn.Visible = false;
}
else
{
custIDHidden.Value = _CustomerID.ToString();
AddBtn.Visible = false;
EditBtn.Visible = true;
}
if (!Page.IsPostBack)
{
if (_CustomerID != 0)
{
string selectQuery = "BillToRegion, BillToCountry FROM Customers WHERE CustomerID = @CustomerID";
try
{
using (SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["AbleCommerce"].ToString()))
{
cn.Open();
SqlCommand cmd = new SqlCommand(selectQuery, cn);
cmd.Parameters.Add(new SqlParameter("@CustomerID", custIDHidden.Value));
using (IDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
ProvinceCode.SelectedValue = reader["BillToRegion"].ToString();
CountryCode.SelectedValue = reader["BillToCountry"].ToString();
}
}
cn.Close();
}
}
catch (Exception x)
{
Logger.Warn("Admin\\People\\Customers\\EditCustomer.aspx - Page_Load", x);
}
}
}
}