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Page.PreviousPage Property

Definition

Gets the page that transferred control to the current page.

public:
 property System::Web::UI::Page ^ PreviousPage { System::Web::UI::Page ^ get(); };
[System.ComponentModel.Browsable(false)]
public System.Web.UI.Page PreviousPage { get; }
[<System.ComponentModel.Browsable(false)>]
member this.PreviousPage : System.Web.UI.Page
Public ReadOnly Property PreviousPage As Page

Property Value

The Page representing the page that transferred control to the current page.

Attributes

Exceptions

The current user is not allowed to access the previous page.

-or-

ASP.NET routing is in use and the previous page's URL is a routed URL. When ASP.NET checks access permissions, it assumes that the URL is an actual path to a file. Because this is not the case with a routed URL, the check fails.

Examples

The following example is in two parts. The first is an ASP.NET page that uses the Transfer method, exposed in the page model as Server.Transfer("path"). The second part is the target page, which uses the PreviousPage property to get the title of the first page.

<%@ 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 Page_Load(object sender, EventArgs e)
    {
        // If second is an even number, the server is available
        // Replace this line with a valid check for the server.
        bool IsServerAvailable = (DateTime.Now.Second % 2 == 0);
        
        if (!IsServerAvailable)
            Server.Transfer("Notify.aspx", true);
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Switch Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <h2>Database Server is Available</h2>
    
    <p>This page appears if the database server 
        is available.</p>
    
    <p>Enter a pretend Server Name: 
        <asp:TextBox ID="serverNameText" 
        runat="server">MyDatabaseServer</asp:TextBox>
    </p>
    
    <p><asp:Button ID="SubmitButton" runat="server" 
        Text="Is server available?" /></p>
    </div>
    </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 Page_Load(ByVal sender As Object, _
        ByVal e As EventArgs)

        Dim IsServerAvailable As Boolean

        ' If second is an even number, the server is available
        ' Replace this line with a valid check for the server.
        IsServerAvailable = (DateTime.Now.Second Mod 2 = 0)

        If Not IsServerAvailable Then
            Server.Transfer("Notify.aspx", True)
        End If
    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Switch Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <h2>Database Server is Available</h2>
    
    <p>This page appears if the database server 
        is available.</p>
    
    <p>Enter a pretend Server Name: 
        <asp:TextBox ID="serverNameText" 
        runat="server">MyDatabaseServer</asp:TextBox>
    </p>
    
    <p><asp:Button ID="SubmitButton" runat="server" 
        Text="Is server available?" /></p>
    </div>
    </form>
</body>
</html>
<%@ 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 Page_Load(object sender, EventArgs e)
    {
        // Find the server name on the previous page
        TextBox txt = 
                (TextBox)Page.PreviousPage.FindControl("serverNameText");
        if (txt != null)
            prevServerName.Text = Server.HtmlEncode(txt.Text);
        else
            prevServerName.Text = "[Name Not available]";
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Page A</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <h2>Database Server is Not Available</h2>

    <p>This page appears if the named database server is not 
    available, but the URL displays as the main target page.</p>
    
    <p>Server Name (From Page.PreviousPage): 
        <asp:Label ID="prevServerName" runat="server" /></p>
    
    <p>Refresh the page to see if the server is now available.</p>
    </div>
    </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 Page_Load(ByVal sender As Object, _
        ByVal e As EventArgs)

        Dim txt As TextBox

        ' Find the server name on the previous page
        txt = CType(Page.PreviousPage.FindControl _
            ("serverNameText"), TextBox)
        If Not IsNothing(txt) Then
            prevServerName.Text = Server.HtmlEncode(txt.Text)
        Else
            prevServerName.Text = "[Name Not available]"
        End If
    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Page A</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <h2>Database Server is Not Available</h2>

    <p>This page appears if the named database server is not 
    available, but the URL displays as the main target page.</p>
    
    <p>Server Name (From Page.PreviousPage): 
        <asp:Label ID="prevServerName" runat="server" /></p>
    
    <p>Refresh the page to see if the server is now available.</p>
    </div>
    </form>
</body>
</html>

Remarks

When you use the Transfer method or use cross-page posting to transfer processing from one ASP.NET page to another, the originating page contains request information that might be required for the destination page. You can use the PreviousPage property to access that information.

If the current page is being rendered as a result of a direct request (not a transfer or cross-post from another page), the PreviousPage property contains null.

Applies to