HttpResponse.AddFileDependencies Method

Definition

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

Overloads

AddFileDependencies(ArrayList)

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

AddFileDependencies(String[])

Adds an array of file names to the collection of file names on which the current response is dependent.

AddFileDependencies(ArrayList)

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

public:
 void AddFileDependencies(System::Collections::ArrayList ^ filenames);
public void AddFileDependencies (System.Collections.ArrayList filenames);
member this.AddFileDependencies : System.Collections.ArrayList -> unit
Public Sub AddFileDependencies (filenames As ArrayList)

Parameters

filenames
ArrayList

The collection of files to add.

Examples

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>
<%@ Page Language="vb" %>
<%@ outputcache duration="30" varybyparam="none" %>
<%@ Import Namespace="Samples.AspNet.VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

    Private Sub Page_Load(sender As Object, e As System.EventArgs)
    
       ' Create variable and assign file paths to them.
       Dim file1 As String = Server.MapPath("authors.xml")
       Dim file2 As String = Server.MapPath("books.xml")
    
       ' Create an array list to contain the file paths.
       Dim fileList As New ArrayList()
       fileList.Add(file1)
       fileList.Add(file2)
    
       ' Use the AddFileDependencies method to
       ' invalidate the output cached page if 
       ' one of the files changes.
       Response.AddFileDependencies(fileList)
    
       ' Populate the DataGrids.
       dgAuthors.DataSource = DataHelper.GetAuthorData()
       dgAuthors.DataBind()
    
       dgBooks.DataSource = DataHelper.GetBookData()
       dgBooks.DataBind()
    
       lblOutputCacheMsg.Text = DateTime.Now.ToString()
    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>PageDataDisplay</title>
</head>
<body>
    <form id="Form1" method="post" runat="server">
        <table>
            <tbody>
                <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>
            </tbody>
        </table>
    </form>
</body>
</html>

See also

Applies to

AddFileDependencies(String[])

Adds an array of file names to the collection of file names on which the current response is dependent.

public:
 void AddFileDependencies(cli::array <System::String ^> ^ filenames);
public void AddFileDependencies (string[] filenames);
member this.AddFileDependencies : string[] -> unit
Public Sub AddFileDependencies (filenames As String())

Parameters

filenames
String[]

An array of files to add.

Examples

The following example adds an array of file names to the AddFileDependencies file dependency list. If the files changes, the cached response is invalidated.

<%@ Page Language="C#" %>
<%@ Import namespace="System.IO" %>

<script runat="server">
    private void Page_Load()
    {
        String[] FileNames = new String[3];
        FileNames[0] = "Test.txt";
        FileNames[1] = "Test2.txt";
        FileNames[2] = "Test3.txt";
        Response.AddFileDependencies(FileNames);
        Response.Write("File Dependencies successfully added!");
    }
          
</script>

<%@ Page Language="VB" %>
<%@ Import namespace="System.IO" %>

<script runat="server">
  
    Sub Page_Load()
        Dim FileNames(2) As String
        FileNames(0) = "Test.txt"
        FileNames(1) = "Test2.txt"
        FileNames(2) = "Test3.txt"
        Response.AddFileDependencies(FileNames)
        Response.Write("File Dependencies successfully added!")
    End Sub
          
</script>

See also

Applies to