ListView.Sort(String, SortDirection) Methode
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee sorteert u het ListView besturingselement, afhankelijk van de opgegeven sorteerexpressie en -richting.
public:
virtual void Sort(System::String ^ sortExpression, System::Web::UI::WebControls::SortDirection sortDirection);public virtual void Sort(string sortExpression, System.Web.UI.WebControls.SortDirection sortDirection);abstract member Sort : string * System.Web.UI.WebControls.SortDirection -> unit
override this.Sort : string * System.Web.UI.WebControls.SortDirection -> unitPublic Overridable Sub Sort (sortExpression As String, sortDirection As SortDirection)Parameters
- sortExpression
- String
De sorteerexpressie waarmee het ListView besturingselement moet worden gesorteerd.
- sortDirection
- SortDirection
Een van de SortDirection waarden.
Uitzonderingen
Het ListView besturingselement is gebonden aan een besturingselement voor gegevensbronnen, maar het DataSourceView object dat is gekoppeld aan de gegevensbron is null.
Voorbeelden
In het volgende voorbeeld ziet u hoe u de Sort methode gebruikt om het ListView besturingselement programmatisch te sorteren op meerdere gegevensvelden.
<%@ 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">
// <Snippet2>
void SortButton_Click(Object sender, EventArgs e)
{
// Create the sort expression from the values selected
// by the user from the DropDownList controls. Multiple
// columns can be sorted by creating a sort expression
// that contains a comma-separated list of field names.
String expression = SortList1.SelectedValue + " " +
DirectionList1.SelectedValue + " ," +
SortList2.SelectedValue;
// Determine the sort direction of the second column.
// The sort direction parameter applies only to the
// last column sorted.
SortDirection direction2 = SortDirection.Ascending;
if (DirectionList2.SelectedValue == "DESC")
direction2 = SortDirection.Descending;
// Use the Sort method to programmatically sort the ListView
// control using the sort expression and direction.
ContactsListView.Sort(expression, direction2);
}
// </Snippet2>
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>ListView Sort Example</title>
<style type="text/css">
body { font: 10pt Trebuchet MS; }
</style>
</head>
<body>
<form id="form1" runat="server">
<h3>ListView Sort Example</h3>
<table>
<tr>
<td>Sort by:</td>
<td>
<asp:DropDownList ID="SortList1" runat="server">
<asp:ListItem>ContactID</asp:ListItem>
<asp:ListItem Selected="true">FirstName</asp:ListItem>
<asp:ListItem>LastName</asp:ListItem>
<asp:ListItem>EmailAddress</asp:ListItem>
</asp:DropDownList>
</td>
<td>Sort order:</td>
<td>
<asp:DropDownList ID="DirectionList1" runat="server">
<asp:ListItem Value="ASC" Text="Ascending" Selected="True" />
<asp:ListItem Value="DESC" Text="Descending" />
</asp:DropDownList>
</td>
</tr>
<tr>
<td>Then by:</td>
<td>
<asp:DropDownList ID="SortList2" runat="server">
<asp:ListItem>ContactID</asp:ListItem>
<asp:ListItem>FirstName</asp:ListItem>
<asp:ListItem Selected="true">LastName</asp:ListItem>
<asp:ListItem>EmailAddress</asp:ListItem>
</asp:DropDownList>
</td>
<td>Sort order:</td>
<td>
<asp:DropDownList ID="DirectionList2" runat="server">
<asp:ListItem Value="ASC" Text="Ascending" Selected="True" />
<asp:ListItem Value="DESC" Text="Descending" />
</asp:DropDownList>
</td>
</tr>
</table>
<asp:Button id="SortButton"
Text="Sort"
OnClick="SortButton_Click"
runat="server"/>
<br/><br />
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
runat="server">
<LayoutTemplate>
<table cellpadding="2" width="640px" border="1" runat="server" id="tblContacts">
<tr runat="server">
<th runat="server">ContactID</th>
<th runat="server">FirstName</th>
<th runat="server">LastName</th>
<th runat="server">EmailAddress</th>
</tr>
<tr runat="server" id="itemPlaceholder" />
</table>
<asp:DataPager runat="server" ID="ContactsDataPager" PageSize="12">
<Fields>
<asp:NextPreviousPagerField ButtonType="Button"
ShowFirstPageButton="true"
ShowLastPageButton="true" />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr runat="server">
<td>
<asp:Label ID="ContactIDLabel" runat="server" Text='<%#Eval("ContactID") %>' />
</td>
<td>
<asp:Label ID="FirstNameLabel" runat="server" Text='<%#Eval("FirstName") %>' />
</td>
<td>
<asp:Label ID="LastNameLabel" runat="server" Text='<%#Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailAddressLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
</td>
</tr>
</ItemTemplate>
</asp:ListView>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:SqlDataSource ID="ContactsDataSource" runat="server"
ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
SelectCommand="SELECT [ContactID], [FirstName], [LastName], [EmailAddress]
FROM Person.Contact">
</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">
' <Snippet2>
Sub SortButton_Click(ByVal sender As Object, ByVal e As EventArgs)
' Create the sort expression from the values selected
' by the user from the DropDownList controls. Multiple
' columns can be sorted by creating a sort expression
' that contains a comma-separated list of field names.
Dim expression As String = SortList1.SelectedValue & " " & _
DirectionList1.SelectedValue & " ," & SortList2.SelectedValue
' Determine the sort direction of the second column.
' The sort direction parameter applies only to the
' last column sorted.
Dim direction2 As SortDirection = SortDirection.Ascending
If DirectionList2.SelectedValue = "DESC" Then
direction2 = SortDirection.Descending
End If
' Use the Sort method to programmatically sort the ListView
' control using the sort expression and direction.
ContactsListView.Sort(expression, direction2)
End Sub
' </Snippet2>
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>ListView Sort Example</title>
<style type="text/css">
body { font: 10pt Trebuchet MS; }
</style>
</head>
<body>
<form id="form1" runat="server">
<h3>ListView Sort Example</h3>
<table>
<tr>
<td>Sort by:</td>
<td>
<asp:DropDownList ID="SortList1" runat="server">
<asp:ListItem>ContactID</asp:ListItem>
<asp:ListItem Selected="true">FirstName</asp:ListItem>
<asp:ListItem>LastName</asp:ListItem>
<asp:ListItem>EmailAddress</asp:ListItem>
</asp:DropDownList>
</td>
<td>Sort order:</td>
<td>
<asp:DropDownList ID="DirectionList1" runat="server">
<asp:ListItem Value="ASC" Text="Ascending" Selected="True" />
<asp:ListItem Value="DESC" Text="Descending" />
</asp:DropDownList>
</td>
</tr>
<tr>
<td>Then by:</td>
<td>
<asp:DropDownList ID="SortList2" runat="server">
<asp:ListItem>ContactID</asp:ListItem>
<asp:ListItem>FirstName</asp:ListItem>
<asp:ListItem Selected="true">LastName</asp:ListItem>
<asp:ListItem>EmailAddress</asp:ListItem>
</asp:DropDownList>
</td>
<td>Sort order:</td>
<td>
<asp:DropDownList ID="DirectionList2" runat="server">
<asp:ListItem Value="ASC" Text="Ascending" Selected="True" />
<asp:ListItem Value="DESC" Text="Descending" />
</asp:DropDownList>
</td>
</tr>
</table>
<asp:Button id="SortButton"
Text="Sort"
OnClick="SortButton_Click"
runat="server"/>
<br/><br />
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
runat="server">
<LayoutTemplate>
<table cellpadding="2" width="640px" border="1" runat="server" id="tblContacts">
<tr runat="server">
<th runat="server">ContactID</th>
<th runat="server">FirstName</th>
<th runat="server">LastName</th>
<th runat="server">EmailAddress</th>
</tr>
<tr runat="server" id="itemPlaceholder" />
</table>
<asp:DataPager runat="server" ID="ContactsDataPager" PageSize="12">
<Fields>
<asp:NextPreviousPagerField ButtonType="Button"
ShowFirstPageButton="true"
ShowLastPageButton="true" />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr runat="server">
<td>
<asp:Label ID="ContactIDLabel" runat="server" Text='<%#Eval("ContactID") %>' />
</td>
<td>
<asp:Label ID="FirstNameLabel" runat="server" Text='<%#Eval("FirstName") %>' />
</td>
<td>
<asp:Label ID="LastNameLabel" runat="server" Text='<%#Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailAddressLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
</td>
</tr>
</ItemTemplate>
</asp:ListView>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:SqlDataSource ID="ContactsDataSource" runat="server"
ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
SelectCommand="SELECT [ContactID], [FirstName], [LastName], [EmailAddress]
FROM Person.Contact">
</asp:SqlDataSource>
</form>
</body>
</html>
Opmerkingen
Gebruik de Sort methode om de gegevens die in het ListView besturingselement worden weergegeven programmatisch te sorteren met behulp van de opgegeven sorteerexpressie en -richting. De sorteerexpressie geeft de kolom of kolommen op waarmee moet worden gesorteerd. Als u meerdere kolommen wilt sorteren, maakt u een sorteerexpressie die een door komma's gescheiden lijst met veldnamen bevat. De sorteerrichting geeft aan of sorteren wordt uitgevoerd in oplopende of aflopende volgorde.
Normaal gesproken gebruikt u deze methode als u de inhoud van het ListView besturingselement wilt sorteren van buiten het besturingselement, zoals van een ander besturingselement op de pagina. Deze methode wordt ook gebruikt om programmatisch een standaardsorteervolgorde in te stellen voor het besturingselement wanneer het voor het ListView eerst wordt weergegeven.
Met deze methode worden de Sorted en Sorting gebeurtenissen gegenereerd.
