CommandEventArgs.CommandArgument Proprietà
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Ottiene l'argomento del comando.
public:
property System::Object ^ CommandArgument { System::Object ^ get(); };public object CommandArgument { get; }member this.CommandArgument : objPublic ReadOnly Property CommandArgument As ObjectValore della proprietà
Un oggetto Object contenente l'argomento del comando.
Esempio
Nell'esempio seguente viene illustrato come utilizzare la CommandArgument proprietà per determinare le informazioni supplementari da eseguire per il comando.
<%@ Page Language="C#" AutoEventWireup="True" %>
<!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 runat="server">
<title>Button CommandName Example</title>
<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 id="form1" 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="VB" AutoEventWireup="True" %>
<!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 runat="server">
<title>Button CommandName Example</title>
<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 id="form1" 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>
Commenti
Può CommandArgument contenere qualsiasi stringa impostata dal programmatore. La CommandArgument proprietà integra la CommandName proprietà consentendo di fornire eventuali informazioni aggiuntive per il comando. Ad esempio, è possibile impostare la CommandName proprietà su Sort e impostare la CommandArgument proprietà su per Ascending specificare un comando da ordinare in ordine crescente.