HttpResponse.AddFileDependencies Method (ArrayList)

 

Adds a group of file names to the collection of file names on which the current response is dependent.

Namespace:   System.Web
Assembly:  System.Web (in System.Web.dll)

public void AddFileDependencies(
	ArrayList filenames
)

Parameters

filenames
Type: System.Collections.ArrayList

The collection of files to add.

The following example is an ASP.NET page that is output cached. The code for the page creates an ArrayList of file paths, and then passes the ArrayList as the parameter in a call to the AddFileDependencies method. This makes the output cached response invalid if any of the files specified in the ArrayList changes.

<%@ Page Language="c#" %>
<%@ outputcache duration="30" varybyparam="none" %>
<%@ Import Namespace="Samples.AspNet.CS" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

    private void Page_Load(object sender, System.EventArgs e) 
    {

        // Create variables and assign file paths to them.
        string file1 = Server.MapPath("authors.xml");
        string file2 = Server.MapPath("books.xml");

        // Create an array list to contain the file paths.
        ArrayList fileList = new ArrayList();
        fileList.Add(file1);
    fileList.Add(file2);

        // Make the page dependent upon the arrayList.
        Response.AddFileDependencies(fileList);

        // Populate the DataGrids.
        dgAuthors.DataSource = DataHelper.GetAuthorData();
        dgAuthors.DataBind();

        dgBooks.DataSource = DataHelper.GetBookData();
        dgBooks.DataBind();

        lblOutputCacheMsg.Text = DateTime.Now.ToString();

    }

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>PageDataDisplay</title>
  </head>
  <body>  
    <form id="Form1" method="post" runat="server">
      <table>
        <tr>
          <th style="WIDTH: 118px">
            Authors
          </th>
          <td>
            <asp:DataGrid id="dgAuthors" runat="server"></asp:DataGrid>
          </td>
        </tr>
        <tr>
          <th style="WIDTH: 118px">
            Books
          </th>
          <td>
            <asp:DataGrid id="dgBooks" runat="server"></asp:DataGrid>
          </td>
        </tr>
        <tr>
          <td style="WIDTH: 118px">
            The page was generated at:
          </td>
          <td>
            <asp:Label id="lblOutputCacheMsg" runat="server"></asp:Label>
          </td>
        </tr>
      </table>
    </form>
  </body>
</html>

.NET Framework
Available since 1.1
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