Gridview 每行有 2 个 DropDownLists
2 DropDownLists on each row of Gridview
我有一个基于数据库动态创建的gridview。 gridview 的某些行有 2 个 DropDownLists,而其他行则不依赖于行中的项目。该行的第二个 DropDownList 是根据第一个 DrowpDownMenu 的选择动态创建的。一切正常,除了,如果您在第一行进行选择,然后更改第二行第一个 DropDownList 的选择或单击更新按钮,它将重置第一行的第二个 DropDownList。这显然是由于 PostBack。但我想保持选择直到所有 DropDownLists 都被选中并将更改保存到数据库。任何帮助将不胜感激。
我的网格视图:
<asp:GridView ID="CartList" runat="server" AutoGenerateColumns="False" ShowFooter="True"
GridLines="Vertical" CellPadding="4" CssClass="table table-striped table-bordered"
OnRowDataBound="CartList_RowDataBound">
<Columns>
<asp:BoundField DataField="ProductID" HeaderText="ID" SortExpression="ProductID" />
<asp:BoundField DataField="Product.ProductName" HeaderText="Name" />
<asp:BoundField DataField="Product.UnitPrice" HeaderText="Price (each)" DataFormatString="{0:c}" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox ID="PurchaseQuantity" Width="40" runat="server" Text='<%# Eval("Quantity") %>'></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Size">
<ItemTemplate>
<asp:DropDownList ID="Sizeddl" runat="server" Font-Size="Medium"
AutoPostBack="true" ForeColor="Black" OnSelectedIndexChanged="Sizeddl_SelectedIndexChanged">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Color">
<ItemTemplate>
<asp:DropDownList ID="ColorNameddl" runat="server"
Font-Size="Medium" ForeColor="Black">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Item Total">
<ItemTemplate>
<%#: String.Format("{0:c}", ((Convert.ToDouble( Eval("Quantity") )) * Convert.ToDouble(Eval("Product.UnitPrice"))))%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Remove Item">
<ItemTemplate>
<asp:CheckBox ID="Remove" runat="server"></asp:CheckBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<div>
<p></p>
<strong>
<asp:Label ID="LabelSubtotal" runat="server" Text="SubTotal: "></asp:Label>
<asp:Label ID="lblSubtotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTax" runat="server" Text="Tax Total: "></asp:Label>
<asp:Label ID="lblTax" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTotalText" runat="server" Text="Order Total: "></asp:Label>
<asp:Label ID="lblTotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
</div>
<br />
<table>
网格视图加载:
DataTable rstSize = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
decimal cartTotal = 0;
cartTotal = usersShoppingCart.GetTotal();
if (cartTotal > 0)
{
// Display Total.
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
}
else
{
lblSubtotal.Text = "";
lblTax.Text = "";
lblTotal.Text = "";
ShoppingCartTitle.InnerText = "Shopping Cart is Empty";
UpdateBtn.Visible = false;
CheckoutImageBtn.Visible = false;
}
if (!IsPostBack)
{
LoadGrid();
}
}
}
void LoadGrid()
{
// Load Cart Items.
using (ShoppingCartActions actions = new ShoppingCartActions())
{
var _db = new ProductContext();
string cartId = actions.GetCartId();
var cart = _db.ShoppingCartItems.Where(
c => c.CartId == cartId).ToList();
// Create DataTable for Colors
rstSize.Columns.Add("SizeName", typeof(string));
var row = rstSize.NewRow();
row["SizeName"] = "S";
row["SizeName"] = "M";
row["SizeName"] = "L";
row["SizeName"] = "XL";
row["SizeName"] = "2XL";
CartList.DataSource = cart;
CartList.DataBind();
// Hide DropDown Lists for rows that they are not needed for.
for (int i = 0; i < CartList.Rows.Count; i++)
{
DropDownList sizeDDL = CartList.Rows[i].FindControl("Sizeddl") as DropDownList;
DropDownList colorDDL = CartList.Rows[i].FindControl("ColorNameddl") as DropDownList;
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
var _prodID = Convert.ToInt32(rowValues["ProductID"]);
var _prod = (from c in _db.Products
where c.ProductID == _prodID
select c.CategoryID).FirstOrDefault();
if (_prod != 1)
{
sizeDDL.Visible = false;
colorDDL.Visible = false;
}
}
}
}
我的 RowDataBound:
protected void CartList_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem;
// Populate and select Color from DB.
DropDownList sizeDDL = (DropDownList)e.Row.FindControl("Sizeddl");
sizeDDL.DataSource = rstSize;
sizeDDL.DataBind();
sizeDDL.Items.Insert(0, new ListItem("Select Size", "0"));
sizeDDL.SelectedValue = gData["SizeName"].ToString();
// Load Color DDL
var _size = sizeDDL.SelectedItem.Text;
int _prod = Convert.ToInt32(e.Row.Cells[0].Text);
var _db = new ProductContext();
var qryColor = (from p in _db.ProductAttributes
join c in _db.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prod
select new { p.ColorID, c.ColorName }).Distinct().ToList();
DropDownList colorDDL = (DropDownList)e.Row.FindControl("ColorNameddl");
// Create DataTable for Colors
DataTable rstColor = new DataTable();
rstColor.Columns.Add("ColorID", typeof(int));
rstColor.Columns.Add("ColorName", typeof(string));
foreach(var item in qryColor)
{
var row = rstColor.NewRow();
row["ColorID"] = item.ColorID;
row["ColorName"] = item.ColorName;
rstColor.Rows.Add(row);
}
// Bind Color Drop Down List to DataTable.
colorDDL.DataSource = rstColor;
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.SelectedValue = gData["ColorName"].ToString();
}
}
我的 SelectedIndexChanged
protected void Sizeddl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList sizeDDL = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)sizeDDL.NamingContainer;
string strSize = sizeDDL.SelectedItem.Text;
DropDownList colorDDL = (DropDownList)gRow.FindControl("ColorNameddl");
if (strSize != "Choose one")
{
using (ProductContext context = new ProductContext())
{
int _prodID = Convert.ToInt32(gRow.Cells[0].Text);
var _size = sizeDDL.SelectedItem.Text;
var qryColor = (from p in context.ProductAttributes
join c in context.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prodID
select new { p.ColorID, c.ColorName }).Distinct().ToList();
if (qryColor.Count > 0)
{
colorDDL.DataSource = qryColor;
colorDDL.DataTextField = "ColorName";
colorDDL.DataValueField = "ColorID";
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.Enabled = true;
}
else
{
colorDDL.Items.Clear();
colorDDL.Items.Insert(0, new ListItem("No Colors Available", "0"));
colorDDL.Enabled = false;
}
}
}
}
if you make the selections on the first row
通过“selections”,我们是否假设进行更改 - 或者 select/change 组合框中的值,对吗?
I'd like to maintain the selection until all DropDownLists have been selected and I save the changes to the DB. Any help would be very appreciated.
网格视图将并且应该处理页面上的 post 背面。毕竟,即使在 GV 之外,任何旧按钮或控件都可能并且将会导致 post-backs.
用户没有理由更改任何网格行,包括下拉列表 (DDL) 应该很重要。并且对一行的操作不应影响对其他行的操作。 GV 所谓的“查看”状态是自动的,在大多数情况下您不必担心。
因此,完全不清楚您为什么 post 编辑“添加行”,因为所有这些问题都集中在编辑或更改当前行上。 (对我们来说,比如说下周或任何时候,我们可以查看或处理创建的行,但现在让我们专注于对给定行的更改,以及为什么出于某种原因您会在其他行中看到效果 - 您不应该看到这个。
榜首?
虽然控件 - 包括 GV 可以而且应该毫无问题地处理 post-backs?
如果 post-back 导致网格 re-bind,则情况并非如此。如果发生这种情况,那么您将遇到问题。
那么,榜首?
您遗漏了 how/when/where 您正在加载 GV。
(最重要的部分!!!!)。
下一个?
您不想也不需要在 GV 中显示行 PK id。这些数字不仅对最终用户没有任何意义,而且还存在安全风险 - PK 行号不需要显示,实际上甚至不需要包含在行标记中。我们可以再次将这个问题留到另一天,但您可以(并且应该考虑)使用 DataKeys 进行行 PK id 操作。我们假设数据库中没有重复的 PK row id,对吗?换句话说,请确保您的数据中有一个数据库行 PK“id”。
因此,您以后可以删除该 ProductID。 GV 有一个处理 PK 行 id 的特殊功能——我们应该使用它。 (数据键)
好的,既然我们清理了上面的内容?
在页面加载事件中,我们需要加载 GV,但仅在第一页加载时 - 之后,我们不能 re-load GV(再次绑定),否则您将丢失更改, 并编辑 GV.
此外,您可能需要考虑在底部添加一个保存按钮 - 以保存所有 gv 更改 - 而不是逐行执行此操作。 (但是,这里一次做一件事)。
所以首先,加载 GV 的代码应该在页面加载中。
接下来,该代码只能 运行 第一次。
例如:
if (!IsPostBack)
{
code here to load GV
}
下一个?当 GV 加载该数据时,您需要设置组合框和级联。而且,每行的这种设置应该发生在行数据绑定事件中。
所以,您的 posted 代码看起来没问题,但我们缺少 how/when 您加载 GV。
而且我们也没有看到您的保存按钮。但在这一点上,我会分享您加载 GV 的代码 - 这里缺少所有重要信息。
所以编辑你的问题 - 说明你如何以及何时加载网格 - 缺少。
另外,为什么这里使用行创建事件来设置事件?只需将事件存根和定义放在标记中即可。
您可以随意将飞机简按钮或 DDL 或其他任何东西放入 GV 中。你应该像所有其他控件一样连接事件。
因此,删除该行创建的事件存根 - 它可能会为错误的行连接事件 - 但它不是必需的,并且是一个高风险的冒险。
所以,就这样做:
那么,对于一个按钮,还是GV中的DDL?不能双击按钮(创建点击事件),也不能显示属性sheet添加事件。但是您可以在标记中只输入事件名称,点击“=”,然后注意上面的 intel-sense 是如何弹出一个创建事件的选项的。因此,以这种方式添加事件。在您 select 创建新事件后,您可以转到代码隐藏 - 您会看到新的事件存根,并将您的代码添加到该存根中。 GV 使用内部信息来连接每一行事件 - 你很可能把它搞砸了。
所以,我会删除您添加的行 - 因为我们没有关于该代码的详细信息,并且 how/when 您添加了一行,但是 100% 消除了行创建事件,并连接了一次点击事件将大大消除此处的任何问题 - 如果您的行添加事件“复制”控件,情况尤其如此 - 当您执行此操作时,您可能会复制 DDL 对象,这将再次导致问题。换句话说,您可能有两行相同的对象 - 对其中一行的更改会影响另一行。
所以,转储你的行添加事件,并按照上面的方法直接在 ddl 的标记中添加事件。
那么,对于每一行的按钮,还是其他什么?您仍然可以(并且应该)使用标记来添加这些事件 - 除非没有其他方法,否则不要编写代码这样做。
编辑:工作示例
所以,说这个标记:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
DataKeyNames="ID"
CssClass="table"
Width="30%" OnRowDataBound="GridView1_RowDataBound">
<Columns>
<asp:BoundField DataField="Firstname" HeaderText="Firstname" />
<asp:BoundField DataField="LastName" HeaderText="LastName" />
<asp:TemplateField HeaderText="Select Hotel City">
<ItemTemplate>
<asp:DropDownList ID="cboCity" runat="server" Width="120px" Height="26px"
DataTextField = "City"
DataValueField = "City"
AutoPostback="true"
OnSelectedIndexChanged="cboCity_SelectedIndexChanged"
>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Select Hotel">
<ItemTemplate>
<asp:DropDownList ID="cboHotels" runat="server" Width="210px" Height="26px"
DataValueField ="ID"
DataTextField ="HotelName">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Nights" >
<ItemTemplate>
<asp:TextBox ID="txtNights" runat="server" Style="text-align:right"
Text='<%# Eval("Nights") %>' Width="70px" >
</asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
我们将级联城市组合以限制第二个组合中的酒店。
所以,我们要加载的代码:
DataTable rstCity = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
LoadGrid();
}
void LoadGrid ()
{
// load up City list for combo box - all rows (scope = page)
SqlCommand cmdSQL = new SqlCommand("SELECT City from City ORDER BY City");
rstCity = MyRstP(cmdSQL);
// load up the grid
cmdSQL.CommandText = "SELECT * from People ORDER BY FirstName";
GridView1.DataSource = MyRstP(cmdSQL);
GridView1.DataBind();
}
我们有这个:
注意我们如何不冒险尝试在标记中设置 DDL - 因为我们级联 - 会有太多问题。
因此,我们当然绑定了行数据 - 并且设置了两个 DDL。 (我们设置级联并设置它们的值。
我们有这个:
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem; // get the row data
// load the city combo box
DropDownList cboCity = (DropDownList)e.Row.FindControl("cboCity");
cboCity.DataSource = rstCity;
cboCity.DataBind();
// add blank row for city
cboCity.Items.Insert(0, new ListItem("Select City", ""));
cboCity.SelectedValue = gData["City"].ToString(); // set value of Current city
// now load Hotel combo box - but cascade from above City cbo
string strSQL = @"Select ID, HotelName From tblHotels WHERE City = @City " +
" ORDER BY HotelName";
SqlCommand cmdSQL = new SqlCommand(strSQL);
cmdSQL.Parameters.Add("@City", SqlDbType.NVarChar).Value = gData["HotelCity"].ToString();
DropDownList cboHotels = (DropDownList)e.Row.FindControl("cboHotels");
DataTable rstHotels = MyRstP(cmdSQL);
cboHotels.DataSource = rstHotels;
cboHotels.DataBind();
cboHotels.Items.Insert(0, new ListItem("Select Hotel", ""));
// set hotels combo to current selected
cboHotels.SelectedValue = gData["Hotel_id"].ToString();
}
}
所以,唯一剩下的部分是第一个DDL post-back和级联代码。我们有这个:
protected void cboCity_SelectedIndexChanged(object sender, EventArgs e)
{
// city changed, so cascade Hotel cbo
DropDownList cboCity = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)cboCity.NamingContainer;
// filter hotels to current city
string strCity = cboCity.SelectedItem.Text;
DropDownList cboHotels = (DropDownList)gRow.FindControl("cboHotels");
if (strCity != "Select City")
{
SqlCommand cmdSQL = new
SqlCommand(@"SELECT * from tblHotels WHERE City = @City ORDER BY HotelName");
cmdSQL.Parameters.Add("@City", SqlDbType.NVarChar).Value = strCity;
cboHotels.DataSource = MyRstP(cmdSQL);
cboHotels.DataBind();
cboHotels.Items.Insert(0, new ListItem("Select Hotel", ""));
}
}
所以,有了以上?我看不出某些“其他”行如何可能在这里受到影响(除非您有一些其他代码试图弄乱这些行,或者将一行插入 GV。如果您要插入一行,然后在数据库级别插入 - 和 re-bind GV。但是,插入是一个单独的问题。
这是第二个下拉菜单现在可以正常运行的更新。但是,当您单击更新按钮时,它会正确保存到数据库,但会重置并清除第二个下拉列表。
标记:
<asp:GridView ID="CartList" runat="server" AutoGenerateColumns="False" ShowFooter="True" GridLines="Vertical" CellPadding="4"
ItemType="GetAGrip.Models.CartItem" CssClass="table table-striped table-bordered"
EnableViewState="true">
<Columns>
<asp:BoundField DataField="ProductID" HeaderText="ID" SortExpression="ProductID" />
<asp:BoundField DataField="Product.ProductName" HeaderText="Name" />
<asp:BoundField DataField="Product.UnitPrice" HeaderText="Price (each)" DataFormatString="{0:c}" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox ID="PurchaseQuantity" Width="40" runat="server" Text="<%#: Item.Quantity %>"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Size">
<ItemTemplate>
<asp:DropDownList ID="Sizeddl" runat="server" Font-Size="Medium" OnSelectedIndexChanged="Sizeddl_SelectedIndexChanged"
AutoPostBack="true" ForeColor="Black" SelectedValue="<%#: Item.SizeName %>">
<asp:ListItem Selected="True" Text="Choose one" Value="0"></asp:ListItem>
<asp:ListItem Text="S" Value="S"></asp:ListItem>
<asp:ListItem Text="M" Value="M"></asp:ListItem>
<asp:ListItem Text="L" Value="L"></asp:ListItem>
<asp:ListItem Text="XL" Value="XL"></asp:ListItem>
<asp:ListItem Text="2XL" Value="2XL"></asp:ListItem>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Color">
<ItemTemplate>
<asp:DropDownList ID="ColorNameddl" runat="server" Font-Size="Medium" ForeColor="Black">
</asp:DropDownList>
<asp:Label ID="Templbl" runat="server" Visible="false" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Item Total">
<ItemTemplate>
<%#: String.Format("{0:c}", ((Convert.ToDouble(Item.Quantity)) * Convert.ToDouble(Item.Product.UnitPrice)))%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Remove Item">
<ItemTemplate>
<asp:CheckBox ID="Remove" runat="server"></asp:CheckBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<div>
<p></p>
<strong>
<asp:Label ID="LabelSubtotal" runat="server" Text="SubTotal: "></asp:Label>
<asp:Label ID="lblSubtotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTax" runat="server" Text="Tax Total: "></asp:Label>
<asp:Label ID="lblTax" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTotalText" runat="server" Text="Order Total: "></asp:Label>
<asp:Label ID="lblTotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
</div>
<br />
<table>
<tr>
<td>
<asp:Button ID="UpdateBtn" runat="server" Text="Update" OnClick="UpdateBtn_Click" Visible="false" Enabled="false"/>
</td>
<th colspan="1"> 
</th>
<td>
<asp:ImageButton ID="CheckoutImageBtn" runat="server"
ImageUrl="https://www.paypal.com/en_US/i/btn/btn_xpressCheckout.gif"
Width="145" AlternateText="Check out with PayPal"
OnClick="CheckoutBtn_Click"
BackColor="Transparent" BorderWidth="0" />
</td>
</tr>
</table>
Page_Load
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
LoadGrid();
}
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
decimal cartTotal = 0;
cartTotal = usersShoppingCart.GetTotal();
if (cartTotal > 0)
{
// Display Total.
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
}
else
{
lblSubtotal.Text = "";
lblTax.Text = "";
lblTotal.Text = "";
ShoppingCartTitle.InnerText = "Shopping Cart is Empty";
UpdateBtn.Visible = false;
CheckoutImageBtn.Visible = false;
}
}
}
加载网格、加载第二个下拉列表并在不应出现的行上隐藏 DDL:
void LoadGrid()
{
GetShoppingCartItems();
CartList.DataSource = GetShoppingCartItems();
CartList.DataBind();
var _db = new ProductContext();
for (int i = 0; i < CartList.Rows.Count; i++)
{
DropDownList sizeDDL = CartList.Rows[i].FindControl("Sizeddl") as DropDownList;
DropDownList colorDDL = CartList.Rows[i].FindControl("ColorNameddl") as DropDownList;
var _colors = (from c in _db.Colors
select c.ColorName).Distinct().ToList();
colorDDL.DataSource = _colors;
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.SelectedIndex = 0;
foreach (ListItem item in colorDDL.Items)
{
item.Attributes.Add("disabled", "disabled");
}
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
var _prodID = Convert.ToInt32(rowValues["ProductID"]);
var _prod = (from c in _db.Products
where c.ProductID == _prodID
select c.CategoryID).FirstOrDefault();
if (_prod != 1)
{
sizeDDL.Visible = false;
colorDDL.Visible = false;
}
}
}
GetShoppingCartItems 方法:
public List<CartItem> GetShoppingCartItems()
{
ShoppingCartActions actions = new ShoppingCartActions();
return actions.GetCartItems();
}
UpdateCartItems 方法
public List<CartItem> UpdateCartItems()
{
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
String cartId = usersShoppingCart.GetCartId();
ShoppingCartActions.ShoppingCartUpdates[] cartUpdates = new ShoppingCartActions.ShoppingCartUpdates[CartList.Rows.Count];
for (int i = 0; i < CartList.Rows.Count; i++)
{
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
cartUpdates[i].ProductId = Convert.ToInt32(rowValues["ProductID"]);
CheckBox cbRemove = new CheckBox();
cbRemove = (CheckBox)CartList.Rows[i].FindControl("Remove");
cartUpdates[i].RemoveItem = cbRemove.Checked;
TextBox quantityTextBox = new TextBox();
quantityTextBox = (TextBox)CartList.Rows[i].FindControl("PurchaseQuantity");
cartUpdates[i].PurchaseQuantity = Convert.ToInt16(quantityTextBox.Text.ToString());
DropDownList sizeDropDown = new DropDownList();
sizeDropDown = (DropDownList)CartList.Rows[i].FindControl("Sizeddl");
cartUpdates[i].SizeName = sizeDropDown.Text;
DropDownList colorDropDown = new DropDownList();
colorDropDown = (DropDownList)CartList.Rows[i].FindControl("ColorNameddl");
cartUpdates[i].ColorName = colorDropDown.Text;
}
usersShoppingCart.UpdateShoppingCartDatabase(cartId, cartUpdates);
CartList.DataBind();
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
return usersShoppingCart.GetCartItems();
}
}
获取值字典
public static IOrderedDictionary GetValues(GridViewRow row)
{
IOrderedDictionary values = new OrderedDictionary();
foreach (DataControlFieldCell cell in row.Cells)
{
if (cell.Visible)
{
// Extract values from the cell.
cell.ContainingField.ExtractValuesFromCell(values, cell, row.RowState, true);
}
}
return values;
}
点击更新按钮
protected void UpdateBtn_Click(object sender, EventArgs e)
{
for (int i = 0; i < CartList.Rows.Count; i++)
{
UpdateCartItems();
}
Page.Response.Redirect(Page.Request.Url.ToString(), true);
}
RowDataBound
protected void CartList_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem; // get row data.
// load the color Drop Down List.
DropDownList sizeDDL = (DropDownList)e.Row.FindControl("Sizeddl");
sizeDDL.SelectedValue = gData["SizeName"].ToString();
//// Load Color DDL
var _size = sizeDDL.SelectedItem.Text;
int _prod = Convert.ToInt32(e.Row.Cells[0].Text);
var _db = new ProductContext();
var qryColor = (from p in _db.ProductAttributes
join c in _db.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prod
select new { p.ColorID, c.ColorName }).Distinct().ToList();
DropDownList colorDDL = (DropDownList)e.Row.FindControl("ColorNameddl");
// Bind Color Drop Down List to DataTable.
foreach (ListItem item in colorDDL.Items)
{
if (qryColor.Any(c => c.ColorName == item.ToString()))
{
item.Enabled = true;
}
}
colorDDL.SelectedValue = gData["ColorName"].ToString();
}
}
第一个下拉 SelectedIndexChanged
protected void Sizeddl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList sizeDDL = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)sizeDDL.NamingContainer;
string strSize = sizeDDL.SelectedItem.Text;
DropDownList colorDDL = (DropDownList)gRow.FindControl("ColorNameddl");
if (strSize != "Choose one")
{
using (ProductContext context = new ProductContext())
{
int _prodID = Convert.ToInt32(gRow.Cells[0].Text);
var _size = sizeDDL.SelectedItem.Text;
var qryColor = (from p in context.ProductAttributes
join c in context.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prodID
select new { p.ColorID, c.ColorName }).Distinct().ToList();
if (qryColor.Count > 0)
{
foreach (ListItem item in colorDDL.Items)
{
if (qryColor.Any(c => c.ColorName == item.ToString()))
{
item.Enabled = true;
}
else
{
item.Enabled = false;
}
}
colorDDL.Items[0].Enabled = true;
colorDDL.Enabled = true;
colorDDL.SelectedIndex = 0;
}
else
{
colorDDL.SelectedIndex = 0;
colorDDL.Enabled = false;
}
}
}
}
任何你看到上面没有的方法,那是因为它是我的逻辑文件中的一个方法,用于处理整个应用程序的数据库查询。
我有一个基于数据库动态创建的gridview。 gridview 的某些行有 2 个 DropDownLists,而其他行则不依赖于行中的项目。该行的第二个 DropDownList 是根据第一个 DrowpDownMenu 的选择动态创建的。一切正常,除了,如果您在第一行进行选择,然后更改第二行第一个 DropDownList 的选择或单击更新按钮,它将重置第一行的第二个 DropDownList。这显然是由于 PostBack。但我想保持选择直到所有 DropDownLists 都被选中并将更改保存到数据库。任何帮助将不胜感激。
我的网格视图:
<asp:GridView ID="CartList" runat="server" AutoGenerateColumns="False" ShowFooter="True"
GridLines="Vertical" CellPadding="4" CssClass="table table-striped table-bordered"
OnRowDataBound="CartList_RowDataBound">
<Columns>
<asp:BoundField DataField="ProductID" HeaderText="ID" SortExpression="ProductID" />
<asp:BoundField DataField="Product.ProductName" HeaderText="Name" />
<asp:BoundField DataField="Product.UnitPrice" HeaderText="Price (each)" DataFormatString="{0:c}" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox ID="PurchaseQuantity" Width="40" runat="server" Text='<%# Eval("Quantity") %>'></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Size">
<ItemTemplate>
<asp:DropDownList ID="Sizeddl" runat="server" Font-Size="Medium"
AutoPostBack="true" ForeColor="Black" OnSelectedIndexChanged="Sizeddl_SelectedIndexChanged">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Color">
<ItemTemplate>
<asp:DropDownList ID="ColorNameddl" runat="server"
Font-Size="Medium" ForeColor="Black">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Item Total">
<ItemTemplate>
<%#: String.Format("{0:c}", ((Convert.ToDouble( Eval("Quantity") )) * Convert.ToDouble(Eval("Product.UnitPrice"))))%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Remove Item">
<ItemTemplate>
<asp:CheckBox ID="Remove" runat="server"></asp:CheckBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<div>
<p></p>
<strong>
<asp:Label ID="LabelSubtotal" runat="server" Text="SubTotal: "></asp:Label>
<asp:Label ID="lblSubtotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTax" runat="server" Text="Tax Total: "></asp:Label>
<asp:Label ID="lblTax" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTotalText" runat="server" Text="Order Total: "></asp:Label>
<asp:Label ID="lblTotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
</div>
<br />
<table>
网格视图加载:
DataTable rstSize = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
decimal cartTotal = 0;
cartTotal = usersShoppingCart.GetTotal();
if (cartTotal > 0)
{
// Display Total.
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
}
else
{
lblSubtotal.Text = "";
lblTax.Text = "";
lblTotal.Text = "";
ShoppingCartTitle.InnerText = "Shopping Cart is Empty";
UpdateBtn.Visible = false;
CheckoutImageBtn.Visible = false;
}
if (!IsPostBack)
{
LoadGrid();
}
}
}
void LoadGrid()
{
// Load Cart Items.
using (ShoppingCartActions actions = new ShoppingCartActions())
{
var _db = new ProductContext();
string cartId = actions.GetCartId();
var cart = _db.ShoppingCartItems.Where(
c => c.CartId == cartId).ToList();
// Create DataTable for Colors
rstSize.Columns.Add("SizeName", typeof(string));
var row = rstSize.NewRow();
row["SizeName"] = "S";
row["SizeName"] = "M";
row["SizeName"] = "L";
row["SizeName"] = "XL";
row["SizeName"] = "2XL";
CartList.DataSource = cart;
CartList.DataBind();
// Hide DropDown Lists for rows that they are not needed for.
for (int i = 0; i < CartList.Rows.Count; i++)
{
DropDownList sizeDDL = CartList.Rows[i].FindControl("Sizeddl") as DropDownList;
DropDownList colorDDL = CartList.Rows[i].FindControl("ColorNameddl") as DropDownList;
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
var _prodID = Convert.ToInt32(rowValues["ProductID"]);
var _prod = (from c in _db.Products
where c.ProductID == _prodID
select c.CategoryID).FirstOrDefault();
if (_prod != 1)
{
sizeDDL.Visible = false;
colorDDL.Visible = false;
}
}
}
}
我的 RowDataBound:
protected void CartList_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem;
// Populate and select Color from DB.
DropDownList sizeDDL = (DropDownList)e.Row.FindControl("Sizeddl");
sizeDDL.DataSource = rstSize;
sizeDDL.DataBind();
sizeDDL.Items.Insert(0, new ListItem("Select Size", "0"));
sizeDDL.SelectedValue = gData["SizeName"].ToString();
// Load Color DDL
var _size = sizeDDL.SelectedItem.Text;
int _prod = Convert.ToInt32(e.Row.Cells[0].Text);
var _db = new ProductContext();
var qryColor = (from p in _db.ProductAttributes
join c in _db.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prod
select new { p.ColorID, c.ColorName }).Distinct().ToList();
DropDownList colorDDL = (DropDownList)e.Row.FindControl("ColorNameddl");
// Create DataTable for Colors
DataTable rstColor = new DataTable();
rstColor.Columns.Add("ColorID", typeof(int));
rstColor.Columns.Add("ColorName", typeof(string));
foreach(var item in qryColor)
{
var row = rstColor.NewRow();
row["ColorID"] = item.ColorID;
row["ColorName"] = item.ColorName;
rstColor.Rows.Add(row);
}
// Bind Color Drop Down List to DataTable.
colorDDL.DataSource = rstColor;
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.SelectedValue = gData["ColorName"].ToString();
}
}
我的 SelectedIndexChanged
protected void Sizeddl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList sizeDDL = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)sizeDDL.NamingContainer;
string strSize = sizeDDL.SelectedItem.Text;
DropDownList colorDDL = (DropDownList)gRow.FindControl("ColorNameddl");
if (strSize != "Choose one")
{
using (ProductContext context = new ProductContext())
{
int _prodID = Convert.ToInt32(gRow.Cells[0].Text);
var _size = sizeDDL.SelectedItem.Text;
var qryColor = (from p in context.ProductAttributes
join c in context.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prodID
select new { p.ColorID, c.ColorName }).Distinct().ToList();
if (qryColor.Count > 0)
{
colorDDL.DataSource = qryColor;
colorDDL.DataTextField = "ColorName";
colorDDL.DataValueField = "ColorID";
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.Enabled = true;
}
else
{
colorDDL.Items.Clear();
colorDDL.Items.Insert(0, new ListItem("No Colors Available", "0"));
colorDDL.Enabled = false;
}
}
}
}
if you make the selections on the first row
通过“selections”,我们是否假设进行更改 - 或者 select/change 组合框中的值,对吗?
I'd like to maintain the selection until all DropDownLists have been selected and I save the changes to the DB. Any help would be very appreciated.
网格视图将并且应该处理页面上的 post 背面。毕竟,即使在 GV 之外,任何旧按钮或控件都可能并且将会导致 post-backs.
用户没有理由更改任何网格行,包括下拉列表 (DDL) 应该很重要。并且对一行的操作不应影响对其他行的操作。 GV 所谓的“查看”状态是自动的,在大多数情况下您不必担心。
因此,完全不清楚您为什么 post 编辑“添加行”,因为所有这些问题都集中在编辑或更改当前行上。 (对我们来说,比如说下周或任何时候,我们可以查看或处理创建的行,但现在让我们专注于对给定行的更改,以及为什么出于某种原因您会在其他行中看到效果 - 您不应该看到这个。
榜首?
虽然控件 - 包括 GV 可以而且应该毫无问题地处理 post-backs?
如果 post-back 导致网格 re-bind,则情况并非如此。如果发生这种情况,那么您将遇到问题。
那么,榜首?
您遗漏了 how/when/where 您正在加载 GV。 (最重要的部分!!!!)。
下一个?
您不想也不需要在 GV 中显示行 PK id。这些数字不仅对最终用户没有任何意义,而且还存在安全风险 - PK 行号不需要显示,实际上甚至不需要包含在行标记中。我们可以再次将这个问题留到另一天,但您可以(并且应该考虑)使用 DataKeys 进行行 PK id 操作。我们假设数据库中没有重复的 PK row id,对吗?换句话说,请确保您的数据中有一个数据库行 PK“id”。
因此,您以后可以删除该 ProductID。 GV 有一个处理 PK 行 id 的特殊功能——我们应该使用它。 (数据键)
好的,既然我们清理了上面的内容?
在页面加载事件中,我们需要加载 GV,但仅在第一页加载时 - 之后,我们不能 re-load GV(再次绑定),否则您将丢失更改, 并编辑 GV.
此外,您可能需要考虑在底部添加一个保存按钮 - 以保存所有 gv 更改 - 而不是逐行执行此操作。 (但是,这里一次做一件事)。
所以首先,加载 GV 的代码应该在页面加载中。
接下来,该代码只能 运行 第一次。
例如:
if (!IsPostBack)
{
code here to load GV
}
下一个?当 GV 加载该数据时,您需要设置组合框和级联。而且,每行的这种设置应该发生在行数据绑定事件中。
所以,您的 posted 代码看起来没问题,但我们缺少 how/when 您加载 GV。
而且我们也没有看到您的保存按钮。但在这一点上,我会分享您加载 GV 的代码 - 这里缺少所有重要信息。
所以编辑你的问题 - 说明你如何以及何时加载网格 - 缺少。
另外,为什么这里使用行创建事件来设置事件?只需将事件存根和定义放在标记中即可。
您可以随意将飞机简按钮或 DDL 或其他任何东西放入 GV 中。你应该像所有其他控件一样连接事件。
因此,删除该行创建的事件存根 - 它可能会为错误的行连接事件 - 但它不是必需的,并且是一个高风险的冒险。
所以,就这样做:
那么,对于一个按钮,还是GV中的DDL?不能双击按钮(创建点击事件),也不能显示属性sheet添加事件。但是您可以在标记中只输入事件名称,点击“=”,然后注意上面的 intel-sense 是如何弹出一个创建事件的选项的。因此,以这种方式添加事件。在您 select 创建新事件后,您可以转到代码隐藏 - 您会看到新的事件存根,并将您的代码添加到该存根中。 GV 使用内部信息来连接每一行事件 - 你很可能把它搞砸了。
所以,我会删除您添加的行 - 因为我们没有关于该代码的详细信息,并且 how/when 您添加了一行,但是 100% 消除了行创建事件,并连接了一次点击事件将大大消除此处的任何问题 - 如果您的行添加事件“复制”控件,情况尤其如此 - 当您执行此操作时,您可能会复制 DDL 对象,这将再次导致问题。换句话说,您可能有两行相同的对象 - 对其中一行的更改会影响另一行。
所以,转储你的行添加事件,并按照上面的方法直接在 ddl 的标记中添加事件。
那么,对于每一行的按钮,还是其他什么?您仍然可以(并且应该)使用标记来添加这些事件 - 除非没有其他方法,否则不要编写代码这样做。
编辑:工作示例
所以,说这个标记:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
DataKeyNames="ID"
CssClass="table"
Width="30%" OnRowDataBound="GridView1_RowDataBound">
<Columns>
<asp:BoundField DataField="Firstname" HeaderText="Firstname" />
<asp:BoundField DataField="LastName" HeaderText="LastName" />
<asp:TemplateField HeaderText="Select Hotel City">
<ItemTemplate>
<asp:DropDownList ID="cboCity" runat="server" Width="120px" Height="26px"
DataTextField = "City"
DataValueField = "City"
AutoPostback="true"
OnSelectedIndexChanged="cboCity_SelectedIndexChanged"
>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Select Hotel">
<ItemTemplate>
<asp:DropDownList ID="cboHotels" runat="server" Width="210px" Height="26px"
DataValueField ="ID"
DataTextField ="HotelName">
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Nights" >
<ItemTemplate>
<asp:TextBox ID="txtNights" runat="server" Style="text-align:right"
Text='<%# Eval("Nights") %>' Width="70px" >
</asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
我们将级联城市组合以限制第二个组合中的酒店。
所以,我们要加载的代码:
DataTable rstCity = new DataTable();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
LoadGrid();
}
void LoadGrid ()
{
// load up City list for combo box - all rows (scope = page)
SqlCommand cmdSQL = new SqlCommand("SELECT City from City ORDER BY City");
rstCity = MyRstP(cmdSQL);
// load up the grid
cmdSQL.CommandText = "SELECT * from People ORDER BY FirstName";
GridView1.DataSource = MyRstP(cmdSQL);
GridView1.DataBind();
}
我们有这个:
注意我们如何不冒险尝试在标记中设置 DDL - 因为我们级联 - 会有太多问题。
因此,我们当然绑定了行数据 - 并且设置了两个 DDL。 (我们设置级联并设置它们的值。
我们有这个:
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem; // get the row data
// load the city combo box
DropDownList cboCity = (DropDownList)e.Row.FindControl("cboCity");
cboCity.DataSource = rstCity;
cboCity.DataBind();
// add blank row for city
cboCity.Items.Insert(0, new ListItem("Select City", ""));
cboCity.SelectedValue = gData["City"].ToString(); // set value of Current city
// now load Hotel combo box - but cascade from above City cbo
string strSQL = @"Select ID, HotelName From tblHotels WHERE City = @City " +
" ORDER BY HotelName";
SqlCommand cmdSQL = new SqlCommand(strSQL);
cmdSQL.Parameters.Add("@City", SqlDbType.NVarChar).Value = gData["HotelCity"].ToString();
DropDownList cboHotels = (DropDownList)e.Row.FindControl("cboHotels");
DataTable rstHotels = MyRstP(cmdSQL);
cboHotels.DataSource = rstHotels;
cboHotels.DataBind();
cboHotels.Items.Insert(0, new ListItem("Select Hotel", ""));
// set hotels combo to current selected
cboHotels.SelectedValue = gData["Hotel_id"].ToString();
}
}
所以,唯一剩下的部分是第一个DDL post-back和级联代码。我们有这个:
protected void cboCity_SelectedIndexChanged(object sender, EventArgs e)
{
// city changed, so cascade Hotel cbo
DropDownList cboCity = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)cboCity.NamingContainer;
// filter hotels to current city
string strCity = cboCity.SelectedItem.Text;
DropDownList cboHotels = (DropDownList)gRow.FindControl("cboHotels");
if (strCity != "Select City")
{
SqlCommand cmdSQL = new
SqlCommand(@"SELECT * from tblHotels WHERE City = @City ORDER BY HotelName");
cmdSQL.Parameters.Add("@City", SqlDbType.NVarChar).Value = strCity;
cboHotels.DataSource = MyRstP(cmdSQL);
cboHotels.DataBind();
cboHotels.Items.Insert(0, new ListItem("Select Hotel", ""));
}
}
所以,有了以上?我看不出某些“其他”行如何可能在这里受到影响(除非您有一些其他代码试图弄乱这些行,或者将一行插入 GV。如果您要插入一行,然后在数据库级别插入 - 和 re-bind GV。但是,插入是一个单独的问题。
这是第二个下拉菜单现在可以正常运行的更新。但是,当您单击更新按钮时,它会正确保存到数据库,但会重置并清除第二个下拉列表。
标记:
<asp:GridView ID="CartList" runat="server" AutoGenerateColumns="False" ShowFooter="True" GridLines="Vertical" CellPadding="4"
ItemType="GetAGrip.Models.CartItem" CssClass="table table-striped table-bordered"
EnableViewState="true">
<Columns>
<asp:BoundField DataField="ProductID" HeaderText="ID" SortExpression="ProductID" />
<asp:BoundField DataField="Product.ProductName" HeaderText="Name" />
<asp:BoundField DataField="Product.UnitPrice" HeaderText="Price (each)" DataFormatString="{0:c}" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox ID="PurchaseQuantity" Width="40" runat="server" Text="<%#: Item.Quantity %>"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Size">
<ItemTemplate>
<asp:DropDownList ID="Sizeddl" runat="server" Font-Size="Medium" OnSelectedIndexChanged="Sizeddl_SelectedIndexChanged"
AutoPostBack="true" ForeColor="Black" SelectedValue="<%#: Item.SizeName %>">
<asp:ListItem Selected="True" Text="Choose one" Value="0"></asp:ListItem>
<asp:ListItem Text="S" Value="S"></asp:ListItem>
<asp:ListItem Text="M" Value="M"></asp:ListItem>
<asp:ListItem Text="L" Value="L"></asp:ListItem>
<asp:ListItem Text="XL" Value="XL"></asp:ListItem>
<asp:ListItem Text="2XL" Value="2XL"></asp:ListItem>
</asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Color">
<ItemTemplate>
<asp:DropDownList ID="ColorNameddl" runat="server" Font-Size="Medium" ForeColor="Black">
</asp:DropDownList>
<asp:Label ID="Templbl" runat="server" Visible="false" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Item Total">
<ItemTemplate>
<%#: String.Format("{0:c}", ((Convert.ToDouble(Item.Quantity)) * Convert.ToDouble(Item.Product.UnitPrice)))%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Remove Item">
<ItemTemplate>
<asp:CheckBox ID="Remove" runat="server"></asp:CheckBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<div>
<p></p>
<strong>
<asp:Label ID="LabelSubtotal" runat="server" Text="SubTotal: "></asp:Label>
<asp:Label ID="lblSubtotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTax" runat="server" Text="Tax Total: "></asp:Label>
<asp:Label ID="lblTax" runat="server" EnableViewState="false"></asp:Label>
</strong>
<p></p>
<strong>
<asp:Label ID="LabelTotalText" runat="server" Text="Order Total: "></asp:Label>
<asp:Label ID="lblTotal" runat="server" EnableViewState="false"></asp:Label>
</strong>
</div>
<br />
<table>
<tr>
<td>
<asp:Button ID="UpdateBtn" runat="server" Text="Update" OnClick="UpdateBtn_Click" Visible="false" Enabled="false"/>
</td>
<th colspan="1"> 
</th>
<td>
<asp:ImageButton ID="CheckoutImageBtn" runat="server"
ImageUrl="https://www.paypal.com/en_US/i/btn/btn_xpressCheckout.gif"
Width="145" AlternateText="Check out with PayPal"
OnClick="CheckoutBtn_Click"
BackColor="Transparent" BorderWidth="0" />
</td>
</tr>
</table>
Page_Load
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
LoadGrid();
}
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
decimal cartTotal = 0;
cartTotal = usersShoppingCart.GetTotal();
if (cartTotal > 0)
{
// Display Total.
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
}
else
{
lblSubtotal.Text = "";
lblTax.Text = "";
lblTotal.Text = "";
ShoppingCartTitle.InnerText = "Shopping Cart is Empty";
UpdateBtn.Visible = false;
CheckoutImageBtn.Visible = false;
}
}
}
加载网格、加载第二个下拉列表并在不应出现的行上隐藏 DDL:
void LoadGrid()
{
GetShoppingCartItems();
CartList.DataSource = GetShoppingCartItems();
CartList.DataBind();
var _db = new ProductContext();
for (int i = 0; i < CartList.Rows.Count; i++)
{
DropDownList sizeDDL = CartList.Rows[i].FindControl("Sizeddl") as DropDownList;
DropDownList colorDDL = CartList.Rows[i].FindControl("ColorNameddl") as DropDownList;
var _colors = (from c in _db.Colors
select c.ColorName).Distinct().ToList();
colorDDL.DataSource = _colors;
colorDDL.DataBind();
colorDDL.Items.Insert(0, new ListItem("Select Color", "0"));
colorDDL.SelectedIndex = 0;
foreach (ListItem item in colorDDL.Items)
{
item.Attributes.Add("disabled", "disabled");
}
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
var _prodID = Convert.ToInt32(rowValues["ProductID"]);
var _prod = (from c in _db.Products
where c.ProductID == _prodID
select c.CategoryID).FirstOrDefault();
if (_prod != 1)
{
sizeDDL.Visible = false;
colorDDL.Visible = false;
}
}
}
GetShoppingCartItems 方法:
public List<CartItem> GetShoppingCartItems()
{
ShoppingCartActions actions = new ShoppingCartActions();
return actions.GetCartItems();
}
UpdateCartItems 方法
public List<CartItem> UpdateCartItems()
{
using (ShoppingCartActions usersShoppingCart = new ShoppingCartActions())
{
String cartId = usersShoppingCart.GetCartId();
ShoppingCartActions.ShoppingCartUpdates[] cartUpdates = new ShoppingCartActions.ShoppingCartUpdates[CartList.Rows.Count];
for (int i = 0; i < CartList.Rows.Count; i++)
{
IOrderedDictionary rowValues = new OrderedDictionary();
rowValues = GetValues(CartList.Rows[i]);
cartUpdates[i].ProductId = Convert.ToInt32(rowValues["ProductID"]);
CheckBox cbRemove = new CheckBox();
cbRemove = (CheckBox)CartList.Rows[i].FindControl("Remove");
cartUpdates[i].RemoveItem = cbRemove.Checked;
TextBox quantityTextBox = new TextBox();
quantityTextBox = (TextBox)CartList.Rows[i].FindControl("PurchaseQuantity");
cartUpdates[i].PurchaseQuantity = Convert.ToInt16(quantityTextBox.Text.ToString());
DropDownList sizeDropDown = new DropDownList();
sizeDropDown = (DropDownList)CartList.Rows[i].FindControl("Sizeddl");
cartUpdates[i].SizeName = sizeDropDown.Text;
DropDownList colorDropDown = new DropDownList();
colorDropDown = (DropDownList)CartList.Rows[i].FindControl("ColorNameddl");
cartUpdates[i].ColorName = colorDropDown.Text;
}
usersShoppingCart.UpdateShoppingCartDatabase(cartId, cartUpdates);
CartList.DataBind();
lblSubtotal.Text = String.Format("{0:c}", usersShoppingCart.GetSubtotal());
lblTax.Text = String.Format("{0:c}", usersShoppingCart.GetTax());
lblTotal.Text = String.Format("{0:c}", usersShoppingCart.GetTotal());
return usersShoppingCart.GetCartItems();
}
}
获取值字典
public static IOrderedDictionary GetValues(GridViewRow row)
{
IOrderedDictionary values = new OrderedDictionary();
foreach (DataControlFieldCell cell in row.Cells)
{
if (cell.Visible)
{
// Extract values from the cell.
cell.ContainingField.ExtractValuesFromCell(values, cell, row.RowState, true);
}
}
return values;
}
点击更新按钮
protected void UpdateBtn_Click(object sender, EventArgs e)
{
for (int i = 0; i < CartList.Rows.Count; i++)
{
UpdateCartItems();
}
Page.Response.Redirect(Page.Request.Url.ToString(), true);
}
RowDataBound
protected void CartList_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView gData = (DataRowView)e.Row.DataItem; // get row data.
// load the color Drop Down List.
DropDownList sizeDDL = (DropDownList)e.Row.FindControl("Sizeddl");
sizeDDL.SelectedValue = gData["SizeName"].ToString();
//// Load Color DDL
var _size = sizeDDL.SelectedItem.Text;
int _prod = Convert.ToInt32(e.Row.Cells[0].Text);
var _db = new ProductContext();
var qryColor = (from p in _db.ProductAttributes
join c in _db.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prod
select new { p.ColorID, c.ColorName }).Distinct().ToList();
DropDownList colorDDL = (DropDownList)e.Row.FindControl("ColorNameddl");
// Bind Color Drop Down List to DataTable.
foreach (ListItem item in colorDDL.Items)
{
if (qryColor.Any(c => c.ColorName == item.ToString()))
{
item.Enabled = true;
}
}
colorDDL.SelectedValue = gData["ColorName"].ToString();
}
}
第一个下拉 SelectedIndexChanged
protected void Sizeddl_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList sizeDDL = (DropDownList)sender;
GridViewRow gRow = (GridViewRow)sizeDDL.NamingContainer;
string strSize = sizeDDL.SelectedItem.Text;
DropDownList colorDDL = (DropDownList)gRow.FindControl("ColorNameddl");
if (strSize != "Choose one")
{
using (ProductContext context = new ProductContext())
{
int _prodID = Convert.ToInt32(gRow.Cells[0].Text);
var _size = sizeDDL.SelectedItem.Text;
var qryColor = (from p in context.ProductAttributes
join c in context.Colors
on p.ColorID equals c.ColorID
where p.SizeName == _size & p.ProductID == _prodID
select new { p.ColorID, c.ColorName }).Distinct().ToList();
if (qryColor.Count > 0)
{
foreach (ListItem item in colorDDL.Items)
{
if (qryColor.Any(c => c.ColorName == item.ToString()))
{
item.Enabled = true;
}
else
{
item.Enabled = false;
}
}
colorDDL.Items[0].Enabled = true;
colorDDL.Enabled = true;
colorDDL.SelectedIndex = 0;
}
else
{
colorDDL.SelectedIndex = 0;
colorDDL.Enabled = false;
}
}
}
}
任何你看到上面没有的方法,那是因为它是我的逻辑文件中的一个方法,用于处理整个应用程序的数据库查询。