CommandEventArgs クラス
Command イベントのデータを提供します。
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
.NET Framework のセキュリティ
継承階層
スレッド セーフ
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)
構文解説Command イベントは、Button コントロールまたは ImageButton コントロールがクリックされたときに発生します。
CommandEventArgs オブジェクトには、イベント ハンドラでアクセスできる Command イベントに関するデータが格納されています。CommandEventArgs クラスで使用できるプロパティを使用することにより、Ascending など、コマンドを補足するオプション引数の他に、Sort などの実行するコマンド名を確認できます。
CommandEventArgs のインスタンスの初期プロパティ値の一覧については、CommandEventArgs コンストラクタのトピックを参照してください。
使用例CommandEventArgs のプロパティにアクセスして、実行するコマンドを確認する方法を次の例に示します。この例では、Button コントロールの OnClick プロパティを使用して、イベント ハンドラを宣言によって指定します。
<%@ Page Language="VB" AutoEventWireup="True" %> <html> <head> <script runat="server"> Sub CommandBtn_Click(sender As Object, e As CommandEventArgs) Select e.CommandName Case "Sort" ' Call the method to sort the list. Sort_List(CType(e.CommandArgument, String)) Case "Submit" ' Display a message for the Submit button being clicked. Message.Text = "You clicked the Submit button" ' Test whether the command argument is an empty string (""). If CType(e.CommandArgument , String) = "" Then ' End the message. Message.Text &= "." Else ' Display an error message for the command argument. Message.Text &= ", however the command argument is not recogized." End If Case Else ' The command name is not recognized. Display an error message. Message.Text = "Command name not recogized." End Select End Sub Sub Sort_List(commandArgument As String) Select commandArgument Case "Ascending" ' Insert code to sort the list in ascending order here. Message.Text = "You clicked the Sort Ascending button." Case "Descending" ' Insert code to sort the list in descending order here. Message.Text = "You clicked the Sort Descending button." Case Else ' The command argument is not recognized. Display an error message. Message.Text = "Command argument not recogized." End Select End Sub </script> </head> <body> <form runat="server"> <h3>Button CommandName Example</h3> Click on one of the command buttons. <br><br> <asp:Button id="Button1" Text="Sort Ascending" CommandName="Sort" CommandArgument="Ascending" OnCommand="CommandBtn_Click" runat="server"/> <asp:Button id="Button2" Text="Sort Descending" CommandName="Sort" CommandArgument="Descending" OnCommand="CommandBtn_Click" runat="server"/> <br><br> <asp:Button id="Button3" Text="Submit" CommandName="Submit" OnCommand="CommandBtn_Click" runat="server"/> <asp:Button id="Button4" Text="Unknown Command Name" CommandName="UnknownName" CommandArgument="UnknownArgument" OnCommand="CommandBtn_Click" runat="server"/> <asp:Button id="Button5" Text="Submit Unknown Command Argument" CommandName="Submit" CommandArgument="UnknownArgument" OnCommand="CommandBtn_Click" runat="server"/> <br><br> <asp:Label id="Message" runat="server"/> </form> </body> </html>
<%@ Page Language="C#" AutoEventWireup="True" %> <html> <head> <script runat="server"> void CommandBtn_Click(Object sender, CommandEventArgs e) { switch(e.CommandName) { case "Sort": // Call the method to sort the list. Sort_List((String)e.CommandArgument); break; case "Submit": // Display a message for the Submit button being clicked. Message.Text = "You clicked the Submit button"; // Test whether the command argument is an empty string (""). if((String)e.CommandArgument == "") { // End the message. Message.Text += "."; } else { // Display an error message for the command argument. Message.Text += ", however the command argument is not recogized."; } break; default: // The command name is not recognized. Display an error message. Message.Text = "Command name not recogized."; break; } } void Sort_List(string commandArgument) { switch(commandArgument) { case "Ascending": // Insert code to sort the list in ascending order here. Message.Text = "You clicked the Sort Ascending button."; break; case "Descending": // Insert code to sort the list in descending order here. Message.Text = "You clicked the Sort Descending button."; break; default: // The command argument is not recognized. Display an error message. Message.Text = "Command argument not recogized."; break; } } </script> </head> <body> <form runat="server"> <h3>Button CommandName Example</h3> Click on one of the command buttons. <br><br> <asp:Button id="Button1" Text="Sort Ascending" CommandName="Sort" CommandArgument="Ascending" OnCommand="CommandBtn_Click" runat="server"/> <asp:Button id="Button2" Text="Sort Descending" CommandName="Sort" CommandArgument="Descending" OnCommand="CommandBtn_Click" runat="server"/> <br><br> <asp:Button id="Button3" Text="Submit" CommandName="Submit" OnCommand="CommandBtn_Click" runat="server"/> <asp:Button id="Button4" Text="Unknown Command Name" CommandName="UnknownName" CommandArgument="UnknownArgument" OnCommand="CommandBtn_Click" runat="server"/> <asp:Button id="Button5" Text="Submit Unknown Command Argument" CommandName="Submit" CommandArgument="UnknownArgument" OnCommand="CommandBtn_Click" runat="server"/> <br><br> <asp:Label id="Message" runat="server"/> </form> </body> </html>
Page_Load メソッド内で、イベント ハンドラを指定し、プログラムによってイベントに追加する方法を次のコード例に示します
<%@ Page Language="VB" AutoEventWireup="True" %> <html> <head> <script runat="server"> Sub CommandBtn_Click(sender As Object, e As CommandEventArgs) Select e.CommandName Case "Sort" ' Call the method to sort the list. Sort_List(CType(e.CommandArgument, String)) Case "Submit" ' Display a message for the Submit button being clicked. Message.Text = "You clicked the <b>Submit</b> button" ' Test whether the Command Argument is an empty string (""). If CType(e.CommandArgument , String) = "" Then ' End the message. Message.Text &= "." Else ' Display an error message for the command argument. Message.Text &= ", but the command argument is not recogized." End If Case Else ' The command name is not recognized. Display an error message. Message.Text = "Command name not recogized." End Select End Sub Sub Sort_List(commandArgument As String) Select commandArgument Case "Ascending" ' Insert code to sort the list in ascending order here. Message.Text = "You clicked the <b>Sort Ascending</b> button." Case "Descending" ' Insert code to sort the list in descending order here. Message.Text = "You clicked the <b>Sort Descending</b> button." Case Else ' The command argument is not recognized. Display an error message. Message.Text = "Command argument not recogized." End Select End Sub Sub Page_Load(sender As Object, e As EventArgs) ' Manually register the event-handling method for the Command ' event of the Button controls. AddHandler Button1.Command, AddressOf CommandBtn_Click AddHandler Button2.Command, AddressOf CommandBtn_Click AddHandler Button3.Command, AddressOf CommandBtn_Click AddHandler Button4.Command, AddressOf CommandBtn_Click AddHandler Button5.Command, AddressOf CommandBtn_Click End Sub </script> </head> <body> <form runat="server"> <h3>Button CommandName Example</h3> Click one of the command buttons. <br><br> <asp:Button id="Button1" Text="Sort Ascending" CommandName="Sort" CommandArgument="Ascending" runat="server"/> <asp:Button id="Button2" Text="Sort Descending" CommandName="Sort" CommandArgument="Descending" runat="server"/> <br><br> <asp:Button id="Button3" Text="Submit" CommandName="Submit" runat="server"/> <asp:Button id="Button4" Text="Unknown Command Name" CommandName="UnknownName" CommandArgument="UnknownArgument" runat="server"/> <asp:Button id="Button5" Text="Submit Unknown Command Argument" CommandName="Submit" CommandArgument="UnknownArgument" runat="server"/> <br><br> <asp:Label id="Message" runat="server"/> </form> </body> </html>
<%@ Page Language="C#" AutoEventWireup="True" %> <html> <head> <script runat="server"> void CommandBtn_Click(Object sender, CommandEventArgs e) { switch(e.CommandName) { case "Sort": // Call the method to sort the list. Sort_List((String)e.CommandArgument); break; case "Submit": // Display a message for the Submit button being clicked. Message.Text = "You clicked the <b>Submit</b> button"; // Test whether the Command Argument is an empty string (""). if((String)e.CommandArgument == "") { // End the message. Message.Text += "."; } else { // Display an error message for the command argument. Message.Text += ", but the command argument is not recogized."; } break; default: // The command name is not recognized. Display an error message. Message.Text = "Command name not recogized."; break; } } void Sort_List(string commandArgument) { switch(commandArgument) { case "Ascending": // Insert code to sort the list in ascending order here. Message.Text = "You clicked the <b>Sort Ascending</b> button."; break; case "Descending": // Insert code to sort the list in descending order here. Message.Text = "You clicked the <b>Sort Descending</b> button."; break; default: // The command argument is not recognized. Display an error message. Message.Text = "Command argument not recogized."; break; } } void Page_Load(Object sender, EventArgs e) { // Manually register the event-handling method for the Command // event of the Button controls. Button1.Command += new CommandEventHandler(this.CommandBtn_Click); Button2.Command += new CommandEventHandler(this.CommandBtn_Click); Button3.Command += new CommandEventHandler(this.CommandBtn_Click); Button4.Command += new CommandEventHandler(this.CommandBtn_Click); Button5.Command += new CommandEventHandler(this.CommandBtn_Click); } </script> </head> <body> <form runat="server"> <h3>Button CommandName Example</h3> Click one of the command buttons. <br><br> <asp:Button id="Button1" Text="Sort Ascending" CommandName="Sort" CommandArgument="Ascending" runat="server"/> <asp:Button id="Button2" Text="Sort Descending" CommandName="Sort" CommandArgument="Descending" runat="server"/> <br><br> <asp:Button id="Button3" Text="Submit" CommandName="Submit" runat="server"/> <asp:Button id="Button4" Text="Unknown Command Name" CommandName="UnknownName" CommandArgument="UnknownArgument" runat="server"/> <asp:Button id="Button5" Text="Submit Unknown Command Argument" CommandName="Submit" CommandArgument="UnknownArgument" runat="server"/> <br><br> <asp:Label id="Message" runat="server"/> </form> </body> </html>
.NET Framework のセキュリティ継承階層スレッド セーフプラットフォーム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
開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。
バージョン情報参照- CommandEventArgs クラスのページへのリンク
