ListViewInsertEventArgs Class
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Provides data for the ItemInserting event.
public ref class ListViewInsertEventArgs : System::ComponentModel::CancelEventArgs
public class ListViewInsertEventArgs : System.ComponentModel.CancelEventArgs
type ListViewInsertEventArgs = class
inherit CancelEventArgs
Public Class ListViewInsertEventArgs
Inherits CancelEventArgs
- Inheritance
Examples
The following example shows how to use the ListViewInsertEventArgs object to cancel an insert operation if the data item contains an empty value.
Important
This example contains a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.
<%@ 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()
{
Message.Text = String.Empty;
}
//<Snippet2>
void ContactsListView_ItemInserting(Object sender, ListViewInsertEventArgs e)
{
// Iterate through the values to verify if they are not empty.
foreach (DictionaryEntry de in e.Values)
{
if (de.Value == null)
{
Message.Text = "Cannot insert an empty value.";
e.Cancel = true;
}
}
}
//</Snippet2>
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>ListView.ItemInserting Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>ListView.ItemInserting Example</h3>
<asp:Label ID="Message"
ForeColor="Red"
runat="server"/>
<br/>
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
DataKeyNames="ContactID"
OnItemInserting="ContactsListView_ItemInserting"
InsertItemPosition="LastItem"
runat="server">
<LayoutTemplate>
<table cellpadding="2" border="1" runat="server" id="tblProducts" width="640px">
<tr runat="server" id="itemPlaceholder" />
</table>
<asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
<Fields>
<asp:NextPreviousPagerField
ShowFirstPageButton="true" ShowLastPageButton="true"
FirstPageText="|<< " LastPageText=" >>|"
NextPageText=" > " PreviousPageText=" < " />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr runat="server">
<td valign="top">
<asp:Label ID="FirstNameLabel" runat="server" Text='<%#Eval("FirstName") %>' />
<asp:Label ID="LastNameLabel" runat="server" Text='<%#Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
</td>
</tr>
</ItemTemplate>
<InsertItemTemplate>
<tr style="background-color:#B0C4DE">
<td valign="top">
<asp:Label runat="server" ID="FirstNameLabel"
AssociatedControlID="FirstNameTextBox" Text="First Name"/>
<asp:TextBox ID="FirstNameTextBox" runat="server"
Text='<%#Bind("FirstName") %>' MaxLength="50" /><br />
<asp:Label runat="server" ID="LastNameLabel"
AssociatedControlID="LastNameTextBox" Text="Last Name" />
<asp:TextBox ID="LastNameTextBox" runat="server"
Text='<%#Bind("LastName") %>' MaxLength="50" /><br />
<asp:Label runat="server" ID="EmailLabel"
AssociatedControlID="EmailTextBox" Text="Email" />
<asp:TextBox ID="EmailTextBox" runat="server"
Text='<%#Bind("EmailAddress") %>' MaxLength="50" /><br />
</td>
<td>
<asp:LinkButton ID="InsertButton" runat="server" CommandName="Insert" Text="Insert" />
</td>
</tr>
</InsertItemTemplate>
</asp:ListView>
<asp:SqlDataSource ID="ContactsDataSource" runat="server"
ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
SelectCommand="SELECT [ContactID], [FirstName], [LastName], [EmailAddress]
FROM Person.Contact"
InsertCommand="INSERT INTO Person.Contact
([FirstName], [LastName], [EmailAddress], [PasswordHash], [PasswordSalt])
Values(@FirstName, @LastName, @EmailAddress, '', '');
SELECT @ContactID = SCOPE_IDENTITY()">
<InsertParameters>
<asp:Parameter Name="FirstName" />
<asp:Parameter Name="LastName" />
<asp:Parameter Name="EmailAddress" />
<asp:Parameter Name="ContactID" Type="Int32" Direction="Output" />
</InsertParameters>
</asp:SqlDataSource>
</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()
Message.Text = String.Empty
End Sub
'<Snippet2>
Sub ContactsListView_ItemInserting(ByVal sender As Object, _
ByVal e As ListViewInsertEventArgs)
' Iterate through the values to verify if they are not empty.
For Each de As DictionaryEntry In e.Values
If de.Value Is Nothing Then
Message.Text = "Cannot insert an empty value."
e.Cancel = True
End If
Next
End Sub
'</Snippet2>
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>ListView.ItemInserting Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>ListView.ItemInserting Example</h3>
<asp:Label ID="Message"
ForeColor="Red"
runat="server"/>
<br/>
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
DataKeyNames="ContactID"
OnItemInserting="ContactsListView_ItemInserting"
InsertItemPosition="LastItem"
runat="server">
<LayoutTemplate>
<table cellpadding="2" border="1" runat="server" id="tblProducts" width="640px">
<tr runat="server" id="itemPlaceholder" />
</table>
<asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
<Fields>
<asp:NextPreviousPagerField
ShowFirstPageButton="true" ShowLastPageButton="true"
FirstPageText="|<< " LastPageText=" >>|"
NextPageText=" > " PreviousPageText=" < " />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr runat="server">
<td valign="top">
<asp:Label ID="FirstNameLabel" runat="server" Text='<%#Eval("FirstName") %>' />
<asp:Label ID="LastNameLabel" runat="server" Text='<%#Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
</td>
</tr>
</ItemTemplate>
<InsertItemTemplate>
<tr style="background-color:#B0C4DE">
<td valign="top">
<asp:Label runat="server" ID="FirstNameLabel"
AssociatedControlID="FirstNameTextBox" Text="First Name"/>
<asp:TextBox ID="FirstNameTextBox" runat="server"
Text='<%#Bind("FirstName") %>' MaxLength="50" /><br />
<asp:Label runat="server" ID="LastNameLabel"
AssociatedControlID="LastNameTextBox" Text="Last Name" />
<asp:TextBox ID="LastNameTextBox" runat="server"
Text='<%#Bind("LastName") %>' MaxLength="50" /><br />
<asp:Label runat="server" ID="EmailLabel"
AssociatedControlID="EmailTextBox" Text="Email" />
<asp:TextBox ID="EmailTextBox" runat="server"
Text='<%#Bind("EmailAddress") %>' MaxLength="50" /><br />
</td>
<td>
<asp:LinkButton ID="InsertButton" runat="server" CommandName="Insert" Text="Insert" />
</td>
</tr>
</InsertItemTemplate>
</asp:ListView>
<asp:SqlDataSource ID="ContactsDataSource" runat="server"
ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
SelectCommand="SELECT [ContactID], [FirstName], [LastName], [EmailAddress]
FROM Person.Contact"
InsertCommand="INSERT INTO Person.Contact
([FirstName], [LastName], [EmailAddress], [PasswordHash], [PasswordSalt])
Values(@FirstName, @LastName, @EmailAddress, '', '');
SELECT @ContactID = SCOPE_IDENTITY()">
<InsertParameters>
<asp:Parameter Name="FirstName" />
<asp:Parameter Name="LastName" />
<asp:Parameter Name="EmailAddress" />
<asp:Parameter Name="ContactID" Type="Int32" Direction="Output" />
</InsertParameters>
</asp:SqlDataSource>
</form>
</body>
</html>
Remarks
The ListView control raises the ItemInserting event when an Insert button in the control is clicked, but before the ListView control inserts the record. (An Insert button is a button whose CommandName
property is set to "Insert".) This enables you to provide an event-handling method that performs a custom routine whenever this event occurs. For example, you can validate or HTML-encode the values of a record before it is inserted it in the data source.
A ListViewInsertEventArgs object is passed to the event-handling method. This object enables you to determine the value of an optional command argument that is sent to the ListView control. You can access the ListViewItem object that is being inserted by using the Item property. You can also read or modify the field values for the new record by using the Values property. To cancel the insert operation, set the Cancel property to true
.
For a list of initial property values for an instance of the ListViewInsertEventArgs class, see the ListViewInsertEventArgs constructor.
Constructors
ListViewInsertEventArgs(ListViewItem) |
Initializes a new instance of the ListViewInsertEventArgs class. |
Properties
Cancel |
Gets or sets a value indicating whether the event should be canceled. (Inherited from CancelEventArgs) |
Item |
Gets a ListViewItem object that represents the data item to be inserted. |
Values |
Gets the values for the record to insert. |
Methods
Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
GetHashCode() |
Serves as the default hash function. (Inherited from Object) |
GetType() |
Gets the Type of the current instance. (Inherited from Object) |
MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
ToString() |
Returns a string that represents the current object. (Inherited from Object) |