Редагувати

Поділитися через

ListView.SortExpression Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.Extensions.dll

Gets the sort expression that is associated with the field or fields that are being sorted.

public:
 virtual property System::String ^ SortExpression { System::String ^ get(); };
[System.ComponentModel.Browsable(false)]
public virtual string SortExpression { get; }
[<System.ComponentModel.Browsable(false)>]
member this.SortExpression : string
Public Overridable ReadOnly Property SortExpression As String

Property Value

String

The sort expression that is associated with the field or fields that are being sorted.

Attributes
BrowsableAttribute

Examples

The following example shows how to use the SortExpression property to programmatically determine the column that is being sorted in a ListView control.

<%@ 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">

  protected void ContactsListView_Sorted(object sender, EventArgs e)
  {
    SortExpressionLabel.Text = "Sort Column = " + 
      ContactsListView.SortExpression;
    SortDirectionLabel.Text = "Sort Order = " + 
      ContactsListView.SortDirection.ToString();
  }
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView SortDirection and SortExpression Example</title>
    <style type="text/css">
      body  { font: 10pt Trebuchet MS, Arial, Tahoma; }
      td { border: 1px solid #E6E6FA; }
      .header {	background: #B0C4DE; }
      .alternatingItem { background: #edf5fd; }
    </style>
  </head>
  <body>
    <form id="form1" runat="server">
              
    <h3>SortDirection and SortExpression Example</h3>
      
      <asp:ListView ID="ContactsListView" 
        DataSourceID="ContactsDataSource"
        OnSorted="ContactsListView_Sorted"
        runat="server">
        <LayoutTemplate>
          <table width="640px" runat="server" id="tblContacts">
            <tr class="header" align="center" runat="server">
              <td>
                <asp:LinkButton runat="server" ID="SortByFirstNameButton"
                  CommandName="Sort" Text="First Name" 
                  CommandArgument="FirstName"/>
              </td>
              <td>
                <asp:LinkButton runat="server" ID="SortByLastNameButton"
                  CommandName="Sort" Text="Last Name"
                  CommandArgument="LastName" />
              </td>
              <td>
                <asp:LinkButton runat="server" ID="SortByEmailButton"
                  CommandName="Sort" Text="Email Address" 
                  CommandArgument="EmailAddress" />
              </td>
            </tr>
            <tr runat="server" id="itemPlaceholder" />
          </table>
          <asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
            <Fields>
              <asp:NextPreviousPagerField 
                ShowFirstPageButton="true" 
                ShowLastPageButton="true" />
            </Fields>
          </asp:DataPager>
        </LayoutTemplate>
        <ItemTemplate>
          <tr runat="server">
            <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="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
            </td>
          </tr>
        </ItemTemplate>
        <AlternatingItemTemplate>
          <tr class="alternatingItem" runat="server">
            <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="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
            </td>
          </tr>
        </AlternatingItemTemplate>
      </asp:ListView> <br /><br />

      <asp:Label ID="SortExpressionLabel"
        ForeColor="SteelBlue"
        runat="server"/> <br />
      
      <asp:Label ID="SortDirectionLabel"
        ForeColor="SteelBlue"
        runat="server"/>
        
      <!-- 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">

  Protected Sub ContactsListView_Sorted(ByVal sender As Object, ByVal e As EventArgs)
    
    SortExpressionLabel.Text = "Sort Column = " & ContactsListView.SortExpression
    SortDirectionLabel.Text = "Sort Order = " & ContactsListView.SortDirection.ToString()
    
  End Sub
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView SortDirection and SortExpression Example</title>
    <style type="text/css">
      body  { font: 10pt Trebuchet MS, Arial, Tahoma; }
      td { border: 1px solid #E6E6FA; }
      .header {	background: #B0C4DE; }
      .alternatingItem { background: #edf5fd; }
    </style>
  </head>
  <body>
    <form id="form1" runat="server">
              
    <h3>SortDirection and SortExpression Example</h3>
      
      <asp:ListView ID="ContactsListView" 
        DataSourceID="ContactsDataSource"
        OnSorted="ContactsListView_Sorted"
        runat="server">
        <LayoutTemplate>
          <table width="640px" runat="server" id="tblContacts">
            <tr class="header" align="center" runat="server">
              <td>
                <asp:LinkButton runat="server" ID="SortByFirstNameButton"
                  CommandName="Sort" Text="First Name" 
                  CommandArgument="FirstName"/>
              </td>
              <td>
                <asp:LinkButton runat="server" ID="SortByLastNameButton"
                  CommandName="Sort" Text="Last Name"
                  CommandArgument="LastName" />
              </td>
              <td>
                <asp:LinkButton runat="server" ID="SortByEmailButton"
                  CommandName="Sort" Text="Email Address" 
                  CommandArgument="EmailAddress" />
              </td>
            </tr>
            <tr runat="server" id="itemPlaceholder" />
          </table>
          <asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
            <Fields>
              <asp:NextPreviousPagerField 
                ShowFirstPageButton="true" 
                ShowLastPageButton="true" />
            </Fields>
          </asp:DataPager>
        </LayoutTemplate>
        <ItemTemplate>
          <tr runat="server">
            <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="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
            </td>
          </tr>
        </ItemTemplate>
        <AlternatingItemTemplate>
          <tr class="alternatingItem" runat="server">
            <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="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
            </td>
          </tr>
        </AlternatingItemTemplate>
      </asp:ListView> <br /><br />

      <asp:Label ID="SortExpressionLabel"
        ForeColor="SteelBlue"
        runat="server"/> <br />
      
      <asp:Label ID="SortDirectionLabel"
        ForeColor="SteelBlue"
        runat="server"/>
        
      <!-- 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>

Remarks

When multiple columns are sorted, this property contains a comma-separated list of the fields to sort by.

Applies to

See also