DataListCommandEventArgs 类
定义
重要
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为 CancelCommand 控件的下列事件提供数据：DeleteCommand、EditCommand、ItemCommand、UpdateCommand 和 DataList 事件。 此类不能被继承。
public ref class DataListCommandEventArgs sealed : System::Web::UI::WebControls::CommandEventArgspublic ref class DataListCommandEventArgs : System::Web::UI::WebControls::CommandEventArgspublic sealed class DataListCommandEventArgs : System.Web.UI.WebControls.CommandEventArgspublic class DataListCommandEventArgs : System.Web.UI.WebControls.CommandEventArgstype DataListCommandEventArgs = class
inherit CommandEventArgsPublic NotInheritable Class DataListCommandEventArgs
Inherits CommandEventArgsPublic Class DataListCommandEventArgs
Inherits CommandEventArgs- 继承
示例
下面的示例演示如何为 控件的 EditCommand、 UpdateCommandCancelCommand 和 DeleteCommand 事件DataList定义事件处理程序。 此示例以声明方式指定事件处理程序，并设置控件的每个命令属性的 DataList 事件处理程序。
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>DataList Edit Example</title>
<script runat="server">
// The Cart and CartView objects temporarily store the data source
// for the DataList control while the page is being processed.
DataTable Cart = new DataTable();
DataView CartView;
void Page_Load(Object sender, EventArgs e)
{
// With a database, use an select query to retrieve the data.
// Because the data source in this example is an in-memory
// DataTable, retrieve the data from session state if it exists;
// otherwise, create the data source.
GetSource();
// The DataList control maintains state between posts to the server;
// it only needs to be bound to a data source the first time the
// page is loaded or when the data source is updated.
if (!IsPostBack)
{
BindList();
}
}
void BindList()
{
// Set the data source and bind to the DataList control.
ItemsList.DataSource = CartView;
ItemsList.DataBind();
}
void GetSource()
{
// For this example, the data source is a DataTable that
// is stored in session state. If the data source does not exist,
// create it; otherwise, load the data.
if (Session["ShoppingCart"] == null)
{
// Create the sample data.
DataRow dr;
// Define the columns of the table.
Cart.Columns.Add(new DataColumn("Qty", typeof(Int32)));
Cart.Columns.Add(new DataColumn("Item", typeof(String)));
Cart.Columns.Add(new DataColumn("Price", typeof(Double)));
// Store the table in session state to persist its values
// between posts to the server.
Session["ShoppingCart"] = Cart;
// Populate the DataTable with sample data.
for (int i = 1; i <= 9; i++)
{
dr = Cart.NewRow();
if (i % 2 != 0)
{
dr[0] = 2;
}
else
{
dr[0] = 1;
}
dr[1] = "Item " + i.ToString();
dr[2] = (1.23 * (i + 1));
Cart.Rows.Add(dr);
}
}
else
{
// Retrieve the sample data from session state.
Cart = (DataTable)Session["ShoppingCart"];
}
// Create a DataView and specify the field to sort by.
CartView = new DataView(Cart);
CartView.Sort="Item";
return;
}
void Edit_Command(Object sender, DataListCommandEventArgs e)
{
// Set the EditItemIndex property to the index of the item clicked
// in the DataList control to enable editing for that item. Be sure
// to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = e.Item.ItemIndex;
BindList();
}
void Cancel_Command(Object sender, DataListCommandEventArgs e)
{
// Set the EditItemIndex property to -1 to exit editing mode. Be sure
// to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1;
BindList();
}
void Delete_Command(Object sender, DataListCommandEventArgs e)
{
// Retrieve the name of the item to remove.
String item = ((Label)e.Item.FindControl("ItemLabel")).Text;
// Filter the CartView for the selected item and remove it from
// the data source.
CartView.RowFilter = "Item='" + item + "'";
if (CartView.Count > 0)
{
CartView.Delete(0);
}
CartView.RowFilter = "";
// Set the EditItemIndex property to -1 to exit editing mode. Be sure
// to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1;
BindList();
}
void Update_Command(Object sender, DataListCommandEventArgs e)
{
// Retrieve the updated values from the selected item.
String item = ((Label)e.Item.FindControl("ItemLabel")).Text;
String qty = ((TextBox)e.Item.FindControl("QtyTextBox")).Text;
String price = ((TextBox)e.Item.FindControl("PriceTextBox")).Text;
// With a database, use an update command to update the data.
// Because the data source in this example is an in-memory
// DataTable, delete the old row and replace it with a new one.
// Filter the CartView for the selected item and remove it from
// the data source.
CartView.RowFilter = "Item='" + item + "'";
if (CartView.Count > 0)
{
CartView.Delete(0);
}
CartView.RowFilter = "";
// ***************************************************************
// Insert data validation code here. Make sure to validate the
// values entered by the user before converting to the appropriate
// data types and updating the data source.
// ***************************************************************
// Add a new entry to replace the previous item.
DataRow dr = Cart.NewRow();
dr[0] = qty;
dr[1] = item;
// If necessary, remove the '$' character from the price before
// converting the price to a Double.
if(price[0] == '$')
{
dr[2] = Convert.ToDouble(price.Substring(1));
}
else
{
dr[2] = Convert.ToDouble(price);
}
Cart.Rows.Add(dr);
// Set the EditItemIndex property to -1 to exit editing mode.
// Be sure to rebind the DataList to the data source to refresh
// the control.
ItemsList.EditItemIndex = -1;
BindList();
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>DataList Edit Example</h3>
Click <b>Edit</b> to edit the values of the item.
<br /><br />
<asp:DataList id="ItemsList"
GridLines="Both"
RepeatColumns="3"
RepeatDirection="Horizontal"
CellPadding="3"
CellSpacing="0"
OnEditCommand="Edit_Command"
OnUpdateCommand="Update_Command"
OnDeleteCommand="Delete_Command"
OnCancelCommand="Cancel_Command"
runat="server">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<EditItemStyle BackColor="yellow">
</EditItemStyle>
<HeaderTemplate>
Items
</HeaderTemplate>
<ItemTemplate>
Item:
<%# DataBinder.Eval(Container.DataItem, "Item") %>
<br />
Quantity:
<%# DataBinder.Eval(Container.DataItem, "Qty") %>
<br />
Price:
<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>
<br />
<asp:LinkButton id="EditButton"
Text="Edit"
CommandName="Edit"
runat="server"/>
</ItemTemplate>
<EditItemTemplate>
Item:
<asp:Label id="ItemLabel"
Text='<%# DataBinder.Eval(Container.DataItem, "Item") %>'
runat="server"/>
<br />
Quantity:
<asp:TextBox id="QtyTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Qty") %>'
runat="server"/>
<br />
Price:
<asp:TextBox id="PriceTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>'
runat="server"/>
<br />
<asp:LinkButton id="UpdateButton"
Text="Update"
CommandName="Update"
runat="server"/>
<asp:LinkButton id="DeleteButton"
Text="Delete"
CommandName="Delete"
runat="server"/>
<asp:LinkButton id="CancelButton"
Text="Cancel"
CommandName="Cancel"
runat="server"/>
</EditItemTemplate>
</asp:DataList>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>DataList Edit Example</title>
<script runat="server">
' The Cart and CartView objects temporarily store the data source
' for the DataList control while the page is being processed.
Dim Cart As DataTable = New DataTable()
Dim CartView As DataView
Sub Page_Load(sende As Object, e As EventArgs)
' With a database, use an select query to retrieve the data.
' Because the data source in this example is an in-memory
' DataTable, retrieve the data from session state if it exists;
' otherwise, create the data source.
GetSource()
' The DataGrid control maintains state between posts to the server;
' it only needs to be bound to a data source the first time the
' page is loaded or when the data source is updated.
If Not IsPostBack Then
BindList()
End If
End Sub
Sub BindList()
' Set the data source and bind to the DataList control.
ItemsList.DataSource = CartView
ItemsList.DataBind()
End Sub
Sub GetSource()
' For this example, the data source is a DataTable that
' is stored in session state. If the data source does not exist,
' create it; otherwise, load the data.
If Session("ShoppingCart") Is Nothing Then
' Create the sample data.
Dim dr As DataRow
' Define the columns of the table.
Cart.Columns.Add(new DataColumn("Qty", GetType(Int32)))
Cart.Columns.Add(new DataColumn("Item", GetType(String)))
Cart.Columns.Add(new DataColumn("Price", GetType(Double)))
' Store the table in session state to persist its values
' between posts to the server.
Session("ShoppingCart") = Cart
' Populate the DataTable with sample data.
Dim i As Integer
For i = 1 To 9
dr = Cart.NewRow()
If (i Mod 2) <> 0 Then
dr(0) = 2
Else
dr(0) = 1
End If
dr(1) = "Item " & i.ToString()
dr(2) = (1.23 * (i + 1))
Cart.Rows.Add(dr)
Next i
Else
' Retrieve the sample data from session state.
Cart = CType(Session("ShoppingCart"), DataTable)
End If
' Create a DataView and specify the field to sort by.
CartView = New DataView(Cart)
CartView.Sort="Item"
Return
End Sub
Sub Edit_Command(sender As Object, e As DataListCommandEventArgs)
' Set the EditItemIndex property to the index of the item clicked
' in the DataList control to enable editing for that item. Be sure
' to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = e.Item.ItemIndex
BindList()
End Sub
Sub Cancel_Command(sender As Object, e As DataListCommandEventArgs)
' Set the EditItemIndex property to -1 to exit editing mode. Be sure
' to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1
BindList()
End Sub
Sub Delete_Command(sender As Object, e As DataListCommandEventArgs)
' Retrieve the name of the item to remove.
Dim item As String = (CType(e.Item.FindControl("ItemLabel"), Label)).Text
' Filter the CartView for the selected item and remove it from
' the data source.
CartView.RowFilter = "Item='" & item & "'"
If CartView.Count > 0 Then
CartView.Delete(0)
End If
CartView.RowFilter = ""
' Set the EditItemIndex property to -1 to exit editing mode. Be sure
' to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1
BindList()
End Sub
Sub Update_Command(sender As Object, e As DataListCommandEventArgs)
' Retrieve the updated values from the selected item.
Dim item As String = _
(CType(e.Item.FindControl("ItemLabel"), Label)).Text
Dim qty As String = _
(CType(e.Item.FindControl("QtyTextBox"), TextBox)).Text
Dim price As String = _
(CType(e.Item.FindControl("PriceTextBox"), TextBox)).Text
' With a database, use an update command to update the data.
' Because the data source in this example is an in-memory
' DataTable, delete the old row and replace it with a new one.
' Filter the CartView for the selected item and remove it from
' the data source.
CartView.RowFilter = "Item='" & item & "'"
If CartView.Count > 0 Then
CartView.Delete(0)
End If
CartView.RowFilter = ""
' ***************************************************************
' Insert data validation code here. Make sure to validate the
' values entered by the user before converting to the appropriate
' data types and updating the data source.
' ***************************************************************
' Add a new entry to replace the previous item.
Dim dr As DataRow = Cart.NewRow()
dr(0) = qty
dr(1) = item
' If necessary, remove the '$' character from the price before
' converting the price to a Double.
If price.Chars(0) = "$" Then
dr(2) = Convert.ToDouble(price.Substring(1))
Else
dr(2) = Convert.ToDouble(price)
End If
Cart.Rows.Add(dr)
' Set the EditItemIndex property to -1 to exit editing mode.
' Be sure to rebind the DataList to the data source to refresh
' the control.
ItemsList.EditItemIndex = -1
BindList()
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>DataList Edit Example</h3>
Click <b>Edit</b> to edit the values of the item.
<br /><br />
<asp:DataList id="ItemsList"
GridLines="Both"
RepeatColumns="3"
RepeatDirection="Horizontal"
CellPadding="3"
CellSpacing="0"
OnEditCommand="Edit_Command"
OnUpdateCommand="Update_Command"
OnDeleteCommand="Delete_Command"
OnCancelCommand="Cancel_Command"
runat="server">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<EditItemStyle BackColor="yellow">
</EditItemStyle>
<HeaderTemplate>
Items
</HeaderTemplate>
<ItemTemplate>
Item:
<%# DataBinder.Eval(Container.DataItem, "Item") %>
<br />
Quantity:
<%# DataBinder.Eval(Container.DataItem, "Qty") %>
<br />
Price:
<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>
<br />
<asp:LinkButton id="EditButton"
Text="Edit"
CommandName="Edit"
runat="server"/>
</ItemTemplate>
<EditItemTemplate>
Item:
<asp:Label id="ItemLabel"
Text='<%# DataBinder.Eval(Container.DataItem, "Item") %>'
runat="server"/>
<br />
Quantity:
<asp:TextBox id="QtyTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Qty") %>'
runat="server"/>
<br />
Price:
<asp:TextBox id="PriceTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>'
runat="server"/>
<br />
<asp:LinkButton id="UpdateButton"
Text="Update"
CommandName="Update"
runat="server"/>
<asp:LinkButton id="DeleteButton"
Text="Delete"
CommandName="Delete"
runat="server"/>
<asp:LinkButton id="CancelButton"
Text="Cancel"
CommandName="Cancel"
runat="server"/>
</EditItemTemplate>
</asp:DataList>
</form>
</body>
</html>
下面的示例演示如何指定事件处理程序，以及如何以编程方式将它们添加到 方法中的 Page_Load 事件。
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>DataList Edit Example</title>
<script runat="server">
// The Cart and CartView objects temporarily store the data source
// for the DataList control while the page is being processed.
DataTable Cart = new DataTable();
DataView CartView;
void Page_Load(Object sender, EventArgs e)
{
// With a database, use an select query to retrieve the data.
// Because the data source in this example is an in-memory
// DataTable, retrieve the data from session state if it exists;
// otherwise, create the data source.
GetSource();
// The DataList control maintains state between posts to the server;
// it only needs to be bound to a data source the first time the
// page is loaded or when the data source is updated.
if (!IsPostBack)
{
BindList();
}
// Manually register the event-handling methods.
ItemsList.EditCommand +=
new DataListCommandEventHandler(this.Edit_Command);
ItemsList.UpdateCommand +=
new DataListCommandEventHandler(this.Update_Command);
ItemsList.DeleteCommand +=
new DataListCommandEventHandler(this.Delete_Command);
ItemsList.CancelCommand +=
new DataListCommandEventHandler(this.Cancel_Command);
}
void BindList()
{
// Set the data source and bind to the DataList control.
ItemsList.DataSource = CartView;
ItemsList.DataBind();
}
void GetSource()
{
// For this example, the data source is a DataTable that
// is stored in session state. If the data source does not exist,
// create it; otherwise, load the data.
if (Session["ShoppingCart"] == null)
{
// Create the sample data.
DataRow dr;
// Define the columns of the table.
Cart.Columns.Add(new DataColumn("Qty", typeof(Int32)));
Cart.Columns.Add(new DataColumn("Item", typeof(String)));
Cart.Columns.Add(new DataColumn("Price", typeof(Double)));
// Store the table in session state to persist its values
// between posts to the server.
Session["ShoppingCart"] = Cart;
// Populate the DataTable with sample data.
for (int i = 1; i <= 9; i++)
{
dr = Cart.NewRow();
if (i % 2 != 0)
{
dr[0] = 2;
}
else
{
dr[0] = 1;
}
dr[1] = "Item " + i.ToString();
dr[2] = (1.23 * (i + 1));
Cart.Rows.Add(dr);
}
}
else
{
// Retrieve the sample data from session state.
Cart = (DataTable)Session["ShoppingCart"];
}
// Create a DataView and specify the field to sort by.
CartView = new DataView(Cart);
CartView.Sort="Item";
return;
}
void Edit_Command(Object sender, DataListCommandEventArgs e)
{
// Set the EditItemIndex property to the index of the item clicked
// in the DataList control to enable editing for that item. Be sure
// to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = e.Item.ItemIndex;
BindList();
}
void Cancel_Command(Object sender, DataListCommandEventArgs e)
{
// Set the EditItemIndex property to -1 to exit editing mode. Be sure
// to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1;
BindList();
}
void Delete_Command(Object sender, DataListCommandEventArgs e)
{
// Retrieve the name of the item to remove.
String item = ((Label)e.Item.FindControl("ItemLabel")).Text;
// Filter the CartView for the selected item and remove it from
// the data source.
CartView.RowFilter = "Item='" + item + "'";
if (CartView.Count > 0)
{
CartView.Delete(0);
}
CartView.RowFilter = "";
// Set the EditItemIndex property to -1 to exit editing mode. Be sure
// to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1;
BindList();
}
void Update_Command(Object sender, DataListCommandEventArgs e)
{
// Retrieve the updated values from the selected item.
String item = ((Label)e.Item.FindControl("ItemLabel")).Text;
String qty = ((TextBox)e.Item.FindControl("QtyTextBox")).Text;
String price = ((TextBox)e.Item.FindControl("PriceTextBox")).Text;
// With a database, use an update command to update the data.
// Because the data source in this example is an in-memory
// DataTable, delete the old row and replace it with a new one.
// Filter the CartView for the selected item and remove it from
// the data source.
CartView.RowFilter = "Item='" + item + "'";
if (CartView.Count > 0)
{
CartView.Delete(0);
}
CartView.RowFilter = "";
// ***************************************************************
// Insert data validation code here. Make sure to validate the
// values entered by the user before converting to the appropriate
// data types and updating the data source.
// ***************************************************************
// Add a new entry to replace the previous item.
DataRow dr = Cart.NewRow();
dr[0] = qty;
dr[1] = item;
// If necessary, remove the '$' character from the price before
// converting the price to a Double.
if(price[0] == '$')
{
dr[2] = Convert.ToDouble(price.Substring(1));
}
else
{
dr[2] = Convert.ToDouble(price);
}
Cart.Rows.Add(dr);
// Set the EditItemIndex property to -1 to exit editing mode.
// Be sure to rebind the DataList to the data source to refresh
// the control.
ItemsList.EditItemIndex = -1;
BindList();
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>DataList Edit Example</h3>
Click <b>Edit</b> to edit the values of the item.
<br /><br />
<asp:DataList id="ItemsList"
GridLines="Both"
RepeatColumns="3"
RepeatDirection="Horizontal"
CellPadding="3"
CellSpacing="0"
runat="server">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<EditItemStyle BackColor="yellow">
</EditItemStyle>
<HeaderTemplate>
Items
</HeaderTemplate>
<ItemTemplate>
Item:
<%# DataBinder.Eval(Container.DataItem, "Item") %>
<br />
Quantity:
<%# DataBinder.Eval(Container.DataItem, "Qty") %>
<br />
Price:
<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>
<br />
<asp:LinkButton id="EditButton"
Text="Edit"
CommandName="Edit"
runat="server"/>
</ItemTemplate>
<EditItemTemplate>
Item:
<asp:Label id="ItemLabel"
Text='<%# DataBinder.Eval(Container.DataItem, "Item") %>'
runat="server"/>
<br />
Quantity:
<asp:TextBox id="QtyTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Qty") %>'
runat="server"/>
<br />
Price:
<asp:TextBox id="PriceTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>'
runat="server"/>
<br />
<asp:LinkButton id="UpdateButton"
Text="Update"
CommandName="Update"
runat="server"/>
<asp:LinkButton id="DeleteButton"
Text="Delete"
CommandName="Delete"
runat="server"/>
<asp:LinkButton id="CancelButton"
Text="Cancel"
CommandName="Cancel"
runat="server"/>
</EditItemTemplate>
</asp:DataList>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>DataList Edit Example</title>
<script runat="server">
' The Cart and CartView objects temporarily store the data source
' for the DataList control while the page is being processed.
Dim Cart As DataTable = New DataTable()
Dim CartView As DataView
Sub Page_Load(sende As Object, e As EventArgs)
' With a database, use an select query to retrieve the data.
' Because the data source in this example is an in-memory
' DataTable, retrieve the data from session state if it exists;
' otherwise, create the data source.
GetSource()
' The DataGrid control maintains state between posts to the server;
' it only needs to be bound to a data source the first time the
' page is loaded or when the data source is updated.
If Not IsPostBack Then
BindList()
End If
' Manually register the event-handling methods.
AddHandler ItemsList.EditCommand, AddressOf Edit_Command
AddHandler ItemsList.UpdateCommand, AddressOf Update_Command
AddHandler ItemsList.DeleteCommand, AddressOf Delete_Command
AddHandler ItemsList.CancelCommand, AddressOf Cancel_Command
End Sub
Sub BindList()
' Set the data source and bind to the DataList control.
ItemsList.DataSource = CartView
ItemsList.DataBind()
End Sub
Sub GetSource()
' For this example, the data source is a DataTable that
' is stored in session state. If the data source does not exist,
' create it; otherwise, load the data.
If Session("ShoppingCart") Is Nothing Then
' Create the sample data.
Dim dr As DataRow
' Define the columns of the table.
Cart.Columns.Add(new DataColumn("Qty", GetType(Int32)))
Cart.Columns.Add(new DataColumn("Item", GetType(String)))
Cart.Columns.Add(new DataColumn("Price", GetType(Double)))
' Store the table in session state to persist its values
' between posts to the server.
Session("ShoppingCart") = Cart
' Populate the DataTable with sample data.
Dim i As Integer
For i = 1 To 9
dr = Cart.NewRow()
If (i Mod 2) <> 0 Then
dr(0) = 2
Else
dr(0) = 1
End If
dr(1) = "Item " & i.ToString()
dr(2) = (1.23 * (i + 1))
Cart.Rows.Add(dr)
Next i
Else
' Retrieve the sample data from session state.
Cart = CType(Session("ShoppingCart"), DataTable)
End If
' Create a DataView and specify the field to sort by.
CartView = New DataView(Cart)
CartView.Sort="Item"
Return
End Sub
Sub Edit_Command(sender As Object, e As DataListCommandEventArgs)
' Set the EditItemIndex property to the index of the item clicked
' in the DataList control to enable editing for that item. Be sure
' to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = e.Item.ItemIndex
BindList()
End Sub
Sub Cancel_Command(sender As Object, e As DataListCommandEventArgs)
' Set the EditItemIndex property to -1 to exit editing mode. Be sure
' to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1
BindList()
End Sub
Sub Delete_Command(sender As Object, e As DataListCommandEventArgs)
' Retrieve the name of the item to remove.
Dim item As String = (CType(e.Item.FindControl("ItemLabel"), Label)).Text
' Filter the CartView for the selected item and remove it from
' the data source.
CartView.RowFilter = "Item='" & item & "'"
If CartView.Count > 0 Then
CartView.Delete(0)
End If
CartView.RowFilter = ""
' Set the EditItemIndex property to -1 to exit editing mode. Be sure
' to rebind the DataList to the data source to refresh the control.
ItemsList.EditItemIndex = -1
BindList()
End Sub
Sub Update_Command(sender As Object, e As DataListCommandEventArgs)
' Retrieve the updated values from the selected item.
Dim item As String = _
(CType(e.Item.FindControl("ItemLabel"), Label)).Text
Dim qty As String = _
(CType(e.Item.FindControl("QtyTextBox"), TextBox)).Text
Dim price As String = _
(CType(e.Item.FindControl("PriceTextBox"), TextBox)).Text
' With a database, use an update command to update the data.
' Because the data source in this example is an in-memory
' DataTable, delete the old row and replace it with a new one.
' Filter the CartView for the selected item and remove it from
' the data source.
CartView.RowFilter = "Item='" & item & "'"
If CartView.Count > 0 Then
CartView.Delete(0)
End If
CartView.RowFilter = ""
' ***************************************************************
' Insert data validation code here. Make sure to validate the
' values entered by the user before converting to the appropriate
' data types and updating the data source.
' ***************************************************************
' Add a new entry to replace the previous item.
Dim dr As DataRow = Cart.NewRow()
dr(0) = qty
dr(1) = item
' If necessary, remove the '$' character from the price before
' converting the price to a Double.
If price.Chars(0) = "$" Then
dr(2) = Convert.ToDouble(price.Substring(1))
Else
dr(2) = Convert.ToDouble(price)
End If
Cart.Rows.Add(dr)
' Set the EditItemIndex property to -1 to exit editing mode.
' Be sure to rebind the DataList to the data source to refresh
' the control.
ItemsList.EditItemIndex = -1
BindList()
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>DataList Edit Example</h3>
Click <b>Edit</b> to edit the values of the item.
<br /><br />
<asp:DataList id="ItemsList"
GridLines="Both"
RepeatColumns="3"
RepeatDirection="Horizontal"
CellPadding="3"
CellSpacing="0"
OnEditCommand="Edit_Command"
OnUpdateCommand="Update_Command"
OnDeleteCommand="Delete_Command"
OnCancelCommand="Cancel_Command"
runat="server">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<AlternatingItemStyle BackColor="Gainsboro">
</AlternatingItemStyle>
<EditItemStyle BackColor="yellow">
</EditItemStyle>
<HeaderTemplate>
Items
</HeaderTemplate>
<ItemTemplate>
Item:
<%# DataBinder.Eval(Container.DataItem, "Item") %>
<br />
Quantity:
<%# DataBinder.Eval(Container.DataItem, "Qty") %>
<br />
Price:
<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>
<br />
<asp:LinkButton id="EditButton"
Text="Edit"
CommandName="Edit"
runat="server"/>
</ItemTemplate>
<EditItemTemplate>
Item:
<asp:Label id="ItemLabel"
Text='<%# DataBinder.Eval(Container.DataItem, "Item") %>'
runat="server"/>
<br />
Quantity:
<asp:TextBox id="QtyTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Qty") %>'
runat="server"/>
<br />
Price:
<asp:TextBox id="PriceTextBox"
Text='<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}") %>'
runat="server"/>
<br />
<asp:LinkButton id="UpdateButton"
Text="Update"
CommandName="Update"
runat="server"/>
<asp:LinkButton id="DeleteButton"
Text="Delete"
CommandName="Delete"
runat="server"/>
<asp:LinkButton id="CancelButton"
Text="Cancel"
CommandName="Cancel"
runat="server"/>
</EditItemTemplate>
</asp:DataList>
</form>
</body>
</html>
注解
单击CancelCommand控件中DataList项的按钮时Cancel，将引发 事件。
单击DeleteCommand控件中DataList项的按钮时Delete，将引发 事件。
单击EditCommand控件中DataList项的按钮时Edit，将引发 事件。
单击 ItemCommand 控件中 DataList 项的任何按钮时，将引发 事件。 这允许你以编程方式测试何时单击特定命令按钮并采取适当的操作。 此事件通常用于处理 控件的 DataList 自定义命令按钮。
单击UpdateCommand控件中DataList项的按钮时Update，将引发 事件。
有关 实例 DataListCommandEventArgs的初始属性值的列表， DataListCommandEventArgs 请参阅 构造函数。
有关如何处理事件的详细信息，请参阅 处理和引发事件。
构造函数
| DataListCommandEventArgs(DataListItem, Object, CommandEventArgs) |
初始化 DataListCommandEventArgs 类的新实例。 |
属性
| CommandArgument |
获取命令的参数。 (继承自 CommandEventArgs) |
| CommandName |
获取命令的名称。 (继承自 CommandEventArgs) |
| CommandSource |
获取命令源。 |
| Item |
获取 DataList 控件中包含命令源的项。 |
方法
| Equals(Object) |
确定指定对象是否等于当前对象。 (继承自 Object) |
| GetHashCode() |
作为默认哈希函数。 (继承自 Object) |
| GetType() |
获取当前实例的 Type。 (继承自 Object) |
| MemberwiseClone() |
创建当前 Object 的浅表副本。 (继承自 Object) |
| ToString() |
返回表示当前对象的字符串。 (继承自 Object) |
