DetailsViewInsertEventHandler Delegát
Definice
Důležité
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Představuje metodu, která zpracovává ItemInserting událost DetailsView ovládacího prvku.
public delegate void DetailsViewInsertEventHandler(System::Object ^ sender, DetailsViewInsertEventArgs ^ e);public delegate void DetailsViewInsertEventHandler(object sender, DetailsViewInsertEventArgs e);type DetailsViewInsertEventHandler = delegate of obj * DetailsViewInsertEventArgs -> unitPublic Delegate Sub DetailsViewInsertEventHandler(sender As Object, e As DetailsViewInsertEventArgs)Parametry
- sender
- Object
Zdroj události
A DetailsViewInsertEventArgs , který obsahuje data události.
Příklady
Následující příklad kódu ukazuje, jak programově přidat DetailsViewInsertEventHandler delegáta ItemInserting 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.AutoGenerateInsertButton = 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.ItemInserting += new DetailsViewInsertEventHandler(this.CustomerDetailsView_ItemInserting);
// Add the DetailsView object to the Controls collection
// of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView);
}
void CustomerDetailsView_ItemInserting(Object sender, DetailsViewInsertEventArgs e)
{
// Use the Values property to retrieve the key field value.
String keyValue = e.Values["CustomerID"].ToString();
// Insert the record only if the key field is four characters
// long; otherwise, cancel the insert operation.
if (keyValue.Length == 4)
{
// Change the key field value to upper case before inserting
// the record in the data source.
e.Values["CustomerID"] = keyValue.ToUpper();
MessageLabel.Text = "";
}
else
{
MessageLabel.Text = "The key field must have four digits.";
e.Cancel = true;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler 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]"
insertcommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
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.AutoGenerateInsertButton = 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.ItemInserting, AddressOf CustomerDetailsView_ItemInserting
' Add the DetailsView object to the Controls collection
' of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView)
End Sub
Sub CustomerDetailsView_ItemInserting(ByVal sender As Object, ByVal e As DetailsViewInsertEventArgs)
' Use the Values property to retrieve the key field value.
Dim keyValue As String = e.Values("CustomerID").ToString()
' Insert the record only if the key field is four characters
' long; otherwise, cancel the insert operation.
If keyValue.Length = 4 Then
' Change the key field value to upper case before inserting
' the record in the data source.
e.Values("CustomerID") = keyValue.ToUpper()
MessageLabel.Text = ""
Else
MessageLabel.Text = "The key field must have four digits."
e.Cancel = True
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler 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]"
insertcommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Následující příklad kódu ukazuje, jak deklarativně přidat DetailsViewInsertEventHandler delegáta ItemInserting 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 CustomerDetailsView_ItemInserting(Object sender,
DetailsViewInsertEventArgs e)
{
// Use the Values property to retrieve the key field value.
String keyValue = e.Values["CustomerID"].ToString();
// Insert the record only if the key field is four characters
// long; otherwise, cancel the insert operation.
if (keyValue.Length == 4)
{
// Change the key field value to upper case before inserting
// the record in the data source.
e.Values["CustomerID"] = keyValue.ToUpper();
MessageLabel.Text = "";
}
else
{
MessageLabel.Text = "The key field must have four digits.";
e.Cancel = true;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
datakeynames="CustomerID"
autogenerateinsertbutton="true"
autogeneraterows="true"
allowpaging="true"
oniteminserting="CustomerDetailsView_ItemInserting"
runat="server">
<fieldheaderstyle backcolor="Navy"
forecolor="White"/>
</asp:detailsview>
<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]"
insertcommand="INSERT INTO [Customers]([CustomerID],
[CompanyName], [Address], [City], [PostalCode],
[Country]) VALUES (@CustomerID, @CompanyName, @Address,
@City, @PostalCode, @Country)"
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_ItemInserting(ByVal sender As Object, _
ByVal e As DetailsViewInsertEventArgs) _
Handles CustomerDetailsView.ItemInserting
' Use the Values property to retrieve the key field value.
Dim keyValue As String = e.Values("CustomerID").ToString()
' Insert the record only if the key field is four characters
' long; otherwise, cancel the insert operation.
If keyValue.Length = 4 Then
' Change the key field value to upper case before inserting
' the record in the data source.
e.Values("CustomerID") = keyValue.ToUpper()
MessageLabel.Text = ""
Else
MessageLabel.Text = "The key field must have four digits."
e.Cancel = True
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
datakeynames="CustomerID"
autogenerateinsertbutton="true"
autogeneraterows="true"
allowpaging="true"
oniteminserting="CustomerDetailsView_ItemInserting"
runat="server">
<fieldheaderstyle backcolor="Navy"
forecolor="White"/>
</asp:detailsview>
<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]"
insertcommand="INSERT INTO [Customers]([CustomerID],
[CompanyName], [Address], [City], [PostalCode],
[Country]) VALUES (@CustomerID, @CompanyName, @Address,
@City, @PostalCode, @Country)"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Poznámky
Ovládací DetailsView prvek vyvolá ItemInserting událost při kliknutí na tlačítko Vložit (tlačítko s CommandName jeho vlastností nastavenou na "Vložit") v rámci ovládacího prvku, ale předtím, než DetailsView ovládací prvek vloží záznam. To vám umožní poskytnout obslužnou rutinu události, která provádí vlastní rutinu, například kódování HTML hodnot záznamu před jeho vložením do zdroje dat, kdykoli dojde k této události.
Při vytváření delegáta DetailsViewInsertEventHandler identifikujete metodu, která bude zpracovávat událost. 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
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