DetailsViewModeEventHandler Delegát
Definice
Důležité
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Představuje metodu, která zpracovává ModeChanging událost ovládacího prvku DetailsView .
public delegate void DetailsViewModeEventHandler(System::Object ^ sender, DetailsViewModeEventArgs ^ e);public delegate void DetailsViewModeEventHandler(object sender, DetailsViewModeEventArgs e);type DetailsViewModeEventHandler = delegate of obj * DetailsViewModeEventArgs -> unitPublic Delegate Sub DetailsViewModeEventHandler(sender As Object, e As DetailsViewModeEventArgs)Parametry
- sender
- Object
Zdroj události
A DetailsViewModeEventArgs , který obsahuje data události.
Příklady
Následující příklad kódu ukazuje, jak programově přidat DetailsViewModeEventHandler delegáta ModeChanging k události DetailsView ovládacího prvku.
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
// Create a new DetailsView object.
DetailsView customerDetailsView = new DetailsView();
// Set the DetailsView object's properties.
customerDetailsView.ID = "CustomerDetailsView";
customerDetailsView.DataSourceID = "DetailsViewSource";
customerDetailsView.AutoGenerateRows = true;
customerDetailsView.AutoGenerateEditButton = true;
customerDetailsView.AllowPaging = true;
customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };
// Programmatically register the event-handling method
// for the ItemInserted event of a DetailsView control.
customerDetailsView.ModeChanging += new DetailsViewModeEventHandler(this.CustomerDetailsView_ModeChanging);
// Add the DetailsView object to the Controls collection
// of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView);
}
void CustomerDetailsView_ModeChanging(Object sender, DetailsViewModeEventArgs e)
{
// Use the sender parameter to access the DetailsView
// control that raised the event.
DetailsView customerDetailsView = (DetailsView)sender;
// Use the NewMode property to determine the mode to which the
// DetailsView control is transitioning.
switch (e.NewMode)
{
case DetailsViewMode.Edit:
// Hide the pager row and clear the Label control
// when transitioning to edit mode.
customerDetailsView.AllowPaging = false;
MessageLabel.Text = "";
break;
case DetailsViewMode.ReadOnly:
// Display the pager row and confirmation message
// when transitioning to edit mode.
customerDetailsView.AllowPaging = true;
if (e.CancelingEdit)
{
MessageLabel.Text = "Update canceled.";
}
else
{
MessageLabel.Text = "Update completed.";
}
break;
case DetailsViewMode.Insert:
// Cancel the mode change if the DetailsView
// control attempts to transition to insert
// mode.
e.Cancel = true;
break;
default:
MessageLabel.Text = "Unsupported mode.";
break;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewModeEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewModeEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:PlaceHolder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the web.config file. -->
<asp:sqldatasource id="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
updatecommand="Update [Customers] Set
[CompanyName]=@CompanyName, [Address]=@Address,
[City]=@City, [PostalCode]=@PostalCode,
[Country]=@Country
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ Page language="VB"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create a new DetailsView object.
Dim customerDetailsView As New DetailsView()
' Set the DetailsView object's properties.
customerDetailsView.ID = "CustomerDetailsView"
customerDetailsView.DataSourceID = "DetailsViewSource"
customerDetailsView.AutoGenerateRows = True
customerDetailsView.AutoGenerateEditButton = True
customerDetailsView.AllowPaging = True
Dim keyArray() As String = {"CustomerID"}
customerDetailsView.DataKeyNames = keyArray
' Programmatically register the event-handling method
' for the ItemInserted event of a DetailsView control.
AddHandler customerDetailsView.ModeChanging, AddressOf CustomerDetailsView_ModeChanging
' Add the DetailsView object to the Controls collection
' of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView)
End Sub
Sub CustomerDetailsView_ModeChanging(ByVal sender As Object, ByVal e As DetailsViewModeEventArgs)
' Use the sender parameter to access the DetailsView
' control that raised the event.
Dim customerDetailsView As DetailsView = CType(sender, DetailsView)
' Use the NewMode property to determine the mode to which the
' DetailsView control is transitioning.
Select Case e.NewMode
Case DetailsViewMode.Edit
' Hide the pager row and clear the Label control
' when transitioning to edit mode.
customerDetailsView.AllowPaging = False
MessageLabel.Text = ""
Case DetailsViewMode.ReadOnly
' Display the pager row and confirmation message
' when transitioning to edit mode.
customerDetailsView.AllowPaging = True
If e.CancelingEdit Then
MessageLabel.Text = "Update canceled."
Else
MessageLabel.Text = "Update completed."
End If
Case DetailsViewMode.Insert
' Cancel the mode change if the DetailsView
' control attempts to transition to insert
' mode.
e.Cancel = True
Case Else
MessageLabel.Text = "Unsupported mode."
End Select
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewModeEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewModeEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:PlaceHolder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the web.config file. -->
<asp:sqldatasource id="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
updatecommand="Update [Customers] Set
[CompanyName]=@CompanyName, [Address]=@Address,
[City]=@City, [PostalCode]=@PostalCode,
[Country]=@Country
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Následující příklad kódu ukazuje, jak deklarativně přidat DetailsViewModeEventHandler delegáta k ModeChanging události DetailsView ovládacího prvku.
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void CustomerDetailsView_ModeChanging(Object sender, DetailsViewModeEventArgs e)
{
// Use the NewMode property to determine the mode to which the
// DetailsView control is transitioning.
switch (e.NewMode)
{
case DetailsViewMode.Edit:
// Hide the pager row and clear the Label control
// when transitioning to edit mode.
CustomerDetailsView.AllowPaging = false;
MessageLabel.Text = "";
break;
case DetailsViewMode.ReadOnly:
// Display the pager row and confirmation message
// when transitioning to edit mode.
CustomerDetailsView.AllowPaging = true;
if (e.CancelingEdit)
{
MessageLabel.Text = "Update canceled.";
}
else
{
MessageLabel.Text = "Update completed.";
}
break;
case DetailsViewMode.Insert:
// Cancel the mode change if the DetailsView
// control attempts to transition to insert
// mode.
e.Cancel = true;
break;
default:
MessageLabel.Text = "Unsupported mode.";
break;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewModeEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewModeEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
datakeynames="CustomerID"
autogeneraterows="true"
autogenerateeditbutton="true"
allowpaging="true"
onmodechanging="CustomerDetailsView_ModeChanging"
runat="server">
</asp:detailsview>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the web.config file. -->
<asp:sqldatasource id="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
updatecommand="Update [Customers] Set
[CompanyName]=@CompanyName, [Address]=@Address,
[City]=@City, [PostalCode]=@PostalCode,
[Country]=@Country
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ Page language="VB" autoeventwireup="false" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub CustomerDetailsView_ModeChanging(ByVal sender As Object, ByVal e As DetailsViewModeEventArgs) Handles CustomerDetailsView.ModeChanging
' Use the NewMode property to determine the mode to which the
' DetailsView control is transitioning.
Select Case e.NewMode
Case DetailsViewMode.Edit
' Hide the pager row and clear the Label control
' when transitioning to edit mode.
CustomerDetailsView.AllowPaging = False
MessageLabel.Text = ""
Case DetailsViewMode.ReadOnly
' Display the pager row and confirmation message
' when transitioning to edit mode.
CustomerDetailsView.AllowPaging = True
If e.CancelingEdit Then
MessageLabel.Text = "Update canceled."
Else
MessageLabel.Text = "Update completed."
End If
Case DetailsViewMode.Insert
' Cancel the mode change if the DetailsView
' control attempts to transition to insert
' mode.
e.Cancel = True
Case Else
MessageLabel.Text = "Unsupported mode."
End Select
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewModeEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewModeEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
datakeynames="CustomerID"
autogeneraterows="true"
autogenerateeditbutton="true"
allowpaging="true"
runat="server">
</asp:detailsview>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the web.config file. -->
<asp:sqldatasource id="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
updatecommand="Update [Customers] Set
[CompanyName]=@CompanyName, [Address]=@Address,
[City]=@City, [PostalCode]=@PostalCode,
[Country]=@Country
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Poznámky
Událost ModeChanging je vyvolána, když se DetailsView ovládací prvek pokusí změnit režim úpravy, vložení a režim jen pro čtení, ale před tím, než se režim skutečně změní. To vám umožní poskytnout obslužnou rutinu události, která provádí vlastní rutinu, například konfiguraci DetailsView ovládacího prvku pro konkrétní režim nebo zrušení změny režimu, kdykoli dojde k této události.
Při vytváření delegáta DetailsViewModeEventHandler identifikujete metodu, která bude událost zpracovávat. Pokud chcete událost přidružit k obslužné rutině události, přidejte do události instanci delegáta. Obslužná rutina události je volána při každém výskytu události, dokud neodeberete delegáta. Další informace o delegátech obslužné rutiny událostí najdete v tématu Zpracování a vyvolávání událostí.
Metody rozšíření
| GetMethodInfo(Delegate) |
Získá objekt, který představuje metodu reprezentovanou zadaným delegátem. |
Platí pro
Viz také
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