This documentation is archived and is not being maintained.

HtmlWindow.IsClosed Property

Note: This property is new in the .NET Framework version 2.0.

Gets a value indicating whether this window is open or closed.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in

public bool IsClosed { get; }
/** @property */
public boolean get_IsClosed ()

public function get IsClosed () : boolean

Property Value

true if the window is still open on the screen; otherwise, false.

If the HtmlWindow has been closed by the user or by way of a call to the Close method, attempting to navigate to a new URL or access the window's document will result in an error. Use this property to determine whether it is safe to call properties and methods on the current window object.

The following code example opens a window, and closes it if the user has not used it in the past five minutes. The code example requires that your form has a WebBrowser control named WebBrowser1, a Button named Button1, and a Timer class named Timer1.

private void ResetFrames()
    if (!(webBrowser1.Document == null)) 
        HtmlElement frameElement = null;
        HtmlWindow docWindow = webBrowser1.Document.Window;

        foreach (HtmlWindow frameWindow in docWindow.Frames)
            frameElement = frameWindow.WindowFrameElement;
            String originalUrl = frameElement.GetAttribute("SRC");

            if (!originalUrl.Equals(frameWindow.Url.ToString())) 
                frameWindow.Navigate(new Uri(originalUrl));

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0