DataListCommandEventArgs.Item プロパティ
DataList コントロールでコマンドのソースを格納している項目を取得します。 名前空間: System.Web.UI.WebControls
アセンブリ: System.Web (system.web.dll 内)
構文
解説
使用例
プラットフォーム
バージョン情報
参照
アセンブリ: System.Web (system.web.dll 内)
構文 プロパティ値
DataList コントロールの選択された項目を表す DataListItem オブジェクト。
DataList コントロールの選択された項目を表す DataListItem オブジェクト。
解説使用例Item プロパティを使用して、DataList コントロールの選択された項目に関する情報を表示する方法の例を次に示します。
<%@ Page Language="VB" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <head> <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 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="C#" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <head> <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 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>
プラットフォームWindows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
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バージョン情報参照- DataListCommandEventArgs.Item プロパティのページへのリンク
