如何在进入页面时获得下拉列表的选定值或索引
本文关键字：下拉列表 索引 | 更新日期: 2023-09-27 17:57:34
我有一个产品订购页面，其中包含中继器内的各种产品选项下拉列表。"添加到购物车"按钮处于"非活动"状态，直到所有选项都有选择为止。从技术上讲，"添加到购物车"按钮有两个图像：一个是灰色图像，当用户没有为产品的所有可用选项选择时使用，另一个是橙色图像，当使用者从每个下拉列表字段中进行选择时使用。这些图像由ShowAddToBasket和HideAddToBascket函数设置。
下拉列表字段的连接在于，来自第一字段的选择将决定对第二字段、有时是第三字段的选择。如果第二个字段不是由第一个字段预先设置的，则第二个域将确定第三个字段的值。第一个下拉列表字段从未被禁用，但其他两个字段可以基于所选的选项。
有一些产品在进入页面时将其所有3个下拉列表都预设为特定选项。这意味着它们都被禁用，用户无法更改。无论用户是否输入数量，"添加到购物车"按钮都不会激活。我一辈子都不知道如何更改它，以便在这种罕见的情况下，一旦输入数量，"添加到购物车"按钮就会自动设置为活动。下拉列表在这些页面中仍然有选择的选项——只是它们是固定的，用户不能更改。
在进入产品页面时，我是否可以获得这些下拉列表字段的选定值或选定索引？我希望能够检查它们是否真的是"空的"，或者它们是否有选择，这样我就可以相应地设置"添加到购物车"按钮。
任何帮助都会很好，因为我真的陷入了困境！：（
下面是代码（我删除了很多不重要的功能）：
protected void Page_Init(object sender, System.EventArgs e)
{
string MyPath = HttpContext.Current.Request.Url.AbsolutePath;
MyPath = MyPath.ToLower();
_Basket = AbleContext.Current.User.Basket;
RedirQryStr = "";
_ProductId = AlwaysConvert.ToInt(Request.QueryString["ProductId"]);
if (Request.QueryString["LineID"] != null)
{
int LineID = Convert.ToInt32(Request.QueryString["LineID"].ToString());
int itemIndex = _Basket.Items.IndexOf(LineID);
BasketItem item = _Basket.Items[itemIndex];
OldWeight.Text = item.Weight.ToString();
OldQty.Text = item.Quantity.ToString();
OldPrice.Text = item.Price.ToString();
}
int UnitMeasure = 0;
SetBaidCustoms(ref UnitMeasure);
GetPrefinishNote();
_ProductId = AlwaysConvert.ToInt(Request.QueryString["ProductId"]);
_Product = ProductDataSource.Load(_ProductId);
if (_Product != null)
{
//GetPercentage();
int _PieceCount = 0;
double _SurchargePercent = 0;
CheckoutHelper.GetItemSurcargePercent(_Product, ref _PieceCount, ref _SurchargePercent);
SurchargePieceCount.Text = _PieceCount.ToString();
SurchargePercent.Text = _SurchargePercent.ToString();
//add weight
BaseWeight.Value = _Product.Weight.ToString();
//DISABLE PURCHASE CONTROLS BY DEFAULT
AddToBasketButton.Visible = false;
rowQuantity.Visible = false;
//HANDLE SKU ROW
trSku.Visible = (ShowSku && (_Product.Sku != string.Empty));
if (trSku.Visible)
{
Sku.Text = _Product.Sku;
}
//HANDLE PART/MODEL NUMBER ROW
trPartNumber.Visible = (ShowPartNumber && (_Product.ModelNumber != string.Empty));
if (trPartNumber.Visible)
{
PartNumber.Text = _Product.ModelNumber;
}
//HANDLE REGPRICE ROW
if (ShowMSRP)
{
decimal msrpWithVAT = TaxHelper.GetShopPrice(_Product.MSRP, _Product.TaxCode != null ? _Product.TaxCode.Id : 0);
if (msrpWithVAT > 0)
{
trRegPrice.Visible = true;
RegPrice.Text = msrpWithVAT.LSCurrencyFormat("ulc");
}
else trRegPrice.Visible = false;
}
else trRegPrice.Visible = false;
// HANDLE PRICES VISIBILITY
if (ShowPrice)
{
if (!_Product.UseVariablePrice)
{
trBasePrice.Visible = true;
BasePrice.Text = _Product.Price.ToString("F2") + BairdLookUp.UnitOfMeasure(UnitMeasure);
trOurPrice.Visible = true;
trVariablePrice.Visible = false;
}
else
{
trOurPrice.Visible = false;
trVariablePrice.Visible = true;
VariablePrice.Text = _Product.Price.ToString("F2");
string varPriceText = string.Empty;
Currency userCurrency = AbleContext.Current.User.UserCurrency;
decimal userLocalMinimum = userCurrency.ConvertFromBase(_Product.MinimumPrice.HasValue ? _Product.MinimumPrice.Value : 0);
decimal userLocalMaximum = userCurrency.ConvertFromBase(_Product.MaximumPrice.HasValue ? _Product.MaximumPrice.Value : 0);
if (userLocalMinimum > 0)
{
if (userLocalMaximum > 0)
{
varPriceText = string.Format("(between {0} and {1})", userLocalMinimum.LSCurrencyFormat("ulcf"), userLocalMaximum.LSCurrencyFormat("ulcf"));
}
else
{
varPriceText = string.Format("(at least {0})", userLocalMinimum.LSCurrencyFormat("ulcf"));
}
}
else if (userLocalMaximum > 0)
{
varPriceText = string.Format("({0} maximum)", userLocalMaximum.LSCurrencyFormat("ulcf"));
}
phVariablePrice.Controls.Add(new LiteralControl(varPriceText));
}
}
//UPDATE QUANTITY LIMITS
if ((_Product.MinQuantity > 0) && (_Product.MaxQuantity > 0))
{
string format = " (min {0}, max {1})";
QuantityLimitsPanel.Controls.Add(new LiteralControl(string.Format(format, _Product.MinQuantity, _Product.MaxQuantity)));
QuantityX.MinValue = _Product.MinQuantity;
QuantityX.MaxValue = _Product.MaxQuantity;
}
else if (_Product.MinQuantity > 0)
{
string format = " (min {0})";
QuantityLimitsPanel.Controls.Add(new LiteralControl(string.Format(format, _Product.MinQuantity)));
QuantityX.MinValue = _Product.MinQuantity;
}
else if (_Product.MaxQuantity > 0)
{
string format = " (max {0})";
QuantityLimitsPanel.Controls.Add(new LiteralControl(string.Format(format, _Product.MaxQuantity)));
QuantityX.MaxValue = _Product.MaxQuantity;
}
if (QuantityX.MinValue > 0) QuantityX.Text = QuantityX.MinValue.ToString();
AddToWishlistButton.Visible = AbleContext.Current.StoreMode == StoreMode.Standard;
}
else
{
this.Controls.Clear();
}
if (!Page.IsPostBack)
{
if (Request.QueryString["Action"] != null)
{
if (Request.QueryString["Action"].ToString().ToLower() == "edit")
{
SetEdit();
}
}
}
}
protected void Page_Load(object sender, System.EventArgs e)
{
if (_Product != null)
{
if (ViewState["OptionDropDownIds"] != null)
{
_OptionDropDownIds = (Hashtable)ViewState["OptionDropDownIds"];
}
else
{
_OptionDropDownIds = new Hashtable();
}
if (ViewState["OptionPickerIds"] != null)
{
_OptionPickerIds = (Hashtable)ViewState["OptionPickerIds"];
}
else
{
_OptionPickerIds = new Hashtable();
}
_SelectedOptionChoices = GetSelectedOptionChoices();
OptionsList.DataSource = GetProductOptions();
OptionsList.DataBind();
//set all to the first value
foreach (RepeaterItem rptItem in OptionsList.Items)
{
DropDownList OptionChoices = (DropDownList)rptItem.FindControl("OptionChoices");
OptionChoices.SelectedIndex = 1;
}
TemplatesList.DataSource = GetProductTemplateFields();
TemplatesList.DataBind();
KitsList.DataSource = GetProductKitComponents();
KitsList.DataBind();
}
if (!Page.IsPostBack)
{
if (_Product.MSRP != 0)
{
salePrice.Visible = true;
RetailPrice.Text = _Product.MSRP.ToString("$0.00");
}
DataSet ds = new DataSet();
DataTable ResultTable = ds.Tables.Add("CatTable");
ResultTable.Columns.Add("OptionID", Type.GetType("System.String"));
ResultTable.Columns.Add("OptionName", Type.GetType("System.String"));
ResultTable.Columns.Add("LinkHeader", Type.GetType("System.String"));
foreach (ProductOption PhOpt in _Product.ProductOptions)
{
string MasterList = GetProductMaster(_ProductId, PhOpt.OptionId);
string PerFootVal = "";
string LinkHeader = "";
string DefaultOption = "no";
string PrefinishMin = "0";
bool VisPlaceholder = true;
ProductDisplayHelper.TestForVariantDependency(ref SlaveHide, _ProductId, PhOpt, ref PrefinishMin, ref PerFootVal, ref LinkHeader, ref VisPlaceholder, ref HasDefault, ref DefaultOption);
if (PrefinishMin == "")
PrefinishMin = "0";
DataRow dr = ResultTable.NewRow();
dr["OptionID"] = PhOpt.OptionId + ":" + MasterList + ":" + PerFootVal + ":" + DefaultOption + ":" + PrefinishMin;
Option _Option = OptionDataSource.Load(PhOpt.OptionId);
dr["OptionName"] = _Option.Name;
dr["LinkHeader"] = LinkHeader;
ResultTable.Rows.Add(dr);
}
//Bind the data to the Repeater
ItemOptions.DataSource = ds;
ItemOptions.DataMember = "CatTable";
ItemOptions.DataBind();
//determine if buttons show
if (ItemOptions.Items.Count == 0)
{
ShowAddToBasket(1);
resetBtn.Visible = true;
}
else
{
HideAddToBasket(3);
}
if (Request.QueryString["Action"] != null)
{
ShowAddToBasket(1);
SetDllAssociation(false);
}
ShowHideDrops();
}
}
private void HideAddToBasket(int Location)
{
AddToBasketButton.Visible = false;
AddToWishlistButton.Visible = false;
resetBtn.Visible = false;
if (Request.QueryString["Action"] == null)
{
SelectAll.Visible = true;
WishGray.Visible = true;
if (Request.QueryString["OrderItemID"] == null)
BasketGray.Visible = true;
else
UpdateButton.Visible = false;
}
else
{
UpdateButton.Visible = true;
NewButtons.Visible = false;
}
if ((_Product.MinQuantity == 1) & (_Product.MaxQuantity == 1))
{
AddToWishlistButton.Visible = false;
BasketGray.Visible = false;
}
}
private void ShowAddToBasket(int place)
{
resetBtn.Visible = true;
if (Request.QueryString["Action"] != null)
{
UpdateButton.Visible = true;
NewButtons.Visible = false;
}
else
{
UpdateButton.Visible = false;
SelectAll.Visible = false;
WishGray.Visible = false;
BasketGray.Visible = false;
if (Request.QueryString["OrderItemID"] == null)
{
AddToBasketButton.Visible = true;
resetBtn.Visible = true;
AddToWishlistButton.Visible = true;
}
else
{
UpdateButton.Visible = true;
AddToBasketButton.Visible = false;
}
}
if ((_Product.MinQuantity == 1) & (_Product.MaxQuantity == 1))
{
AddToWishlistButton.Visible = false;
BasketGray.Visible = false;
resetBtn.Visible = true;
}
}
protected void OptionChoices_DataBound(object sender, EventArgs e)
{
DropDownList ddl = (DropDownList)sender;
if (ddl != null)
{
//bb5.Text = "ddl !=null<br />"; works
List<OptionChoiceItem> ds = (List<OptionChoiceItem>)ddl.DataSource;
if (ds != null && ds.Count > 0)
{
int optionId = ds[0].OptionId;
Option opt = OptionDataSource.Load(optionId);
ShowAddToBasket(4);
OptionChoiceItem oci = ds.FirstOrDefault<OptionChoiceItem>(c => c.Selected);
if (oci != null)
{
ListItem item = ddl.Items.FindByValue(oci.ChoiceId.ToString());
if (item != null)
{
ddl.ClearSelection();
item.Selected = true;
}
}
if (opt != null && !opt.ShowThumbnails)
{
if (!_OptionDropDownIds.Contains(optionId))
{
// bb5.Text = "!_OptionDropDownIds.Contains(optionId)<br />"; works
_OptionDropDownIds.Add(optionId, ddl.UniqueID);
}
if (_SelectedOptionChoices.ContainsKey(optionId))
{
ListItem selectedItem = ddl.Items.FindByValue(_SelectedOptionChoices[optionId].ToString());
if (selectedItem != null)
{
ddl.ClearSelection();
selectedItem.Selected = true;
//bb5.Text = "true: " + selectedItem.Selected.ToString()+"<br />"; doesn't work
}
}
StringBuilder imageScript = new StringBuilder();
imageScript.Append("<script type='"text/javascript'">'n");
imageScript.Append(" var " + ddl.ClientID + "_Images = {};'n");
foreach (OptionChoice choice in opt.Choices)
{
if (!string.IsNullOrEmpty(choice.ImageUrl))
{
imageScript.Append(" " + ddl.ClientID + "_Images[" + choice.Id.ToString() + "] = '" + this.Page.ResolveUrl(choice.ImageUrl) + "';'n");
}
}
imageScript.Append("</script>'n");
ScriptManager scriptManager = ScriptManager.GetCurrent(this.Page);
if (scriptManager != null)
{
ScriptManager.RegisterClientScriptBlock(this, this.GetType(), ddl.ClientID, imageScript.ToString(), false);
}
else
{
Page.ClientScript.RegisterClientScriptBlock(this.GetType(), ddl.ClientID, imageScript.ToString());
}
}
}
ddl.Attributes.Add("onChange", "OptionSelectionChanged('" + ddl.ClientID + "');");
}
}
protected Dictionary<int, int> GetSelectedOptionChoices()
{
HttpRequest request = HttpContext.Current.Request;
Dictionary<int, int> selectedChoices = new Dictionary<int, int>();
if (Page.IsPostBack)
{
foreach (int key in _OptionDropDownIds.Keys)
{
string value = (string)_OptionDropDownIds[key];
Trace.Write(string.Format("Checking For - OptionId:{0} DropDownId:{1}", key, value));
string selectedChoice = request.Form[value];
if (!string.IsNullOrEmpty(selectedChoice))
{
int choiceId = AlwaysConvert.ToInt(selectedChoice);
if (choiceId != 0)
{
Trace.Write(string.Format("Found Selected Choice : {0} - {1}", key, choiceId));
selectedChoices.Add(key, choiceId);
}
}
}
foreach (int key in _OptionPickerIds.Keys)
{
string value = (string)_OptionPickerIds[key];
Trace.Write(string.Format("Checking For - OptionId:{0} PickerId:{1}", key, value));
string selectedChoice = request.Form[value];
if (!string.IsNullOrEmpty(selectedChoice))
{
int choiceId = AlwaysConvert.ToInt(selectedChoice);
if (choiceId != 0)
{
Trace.Write(string.Format("Found Selected Choice : {0} - {1}", key, choiceId));
selectedChoices.Add(key, choiceId);
}
}
}
}
else
{
string optionList = Request.QueryString["Options"];
ShowAddToBasket(2);
if (!string.IsNullOrEmpty(optionList))
{
string[] optionChoices = optionList.Split(',');
if (optionChoices != null)
{
foreach (string optionChoice in optionChoices)
{
OptionChoice choice = OptionChoiceDataSource.Load(AlwaysConvert.ToInt(optionChoice));
if (choice != null)
{
_SelectedOptionChoices.Add(choice.OptionId, choice.Id);
}
}
return _SelectedOptionChoices;
}
}
}
return selectedChoices;
}
protected void SetDDLs(object sender, EventArgs e)
{
bool isRandom = false;
if (LengthDDL.Text != "")
isRandom = true;
SetDllAssociation(isRandom);
}
尝试访问Page_Load事件中的值。我认为Page_Init 中的值还没有绑定