NM_BEFORENAVIGATE

4/8/2010

This notification message is sent by the HTML viewer control before a navigation request to a URL begins.

Syntax

NM_BEFORENAVIGATE
NM_HTMLVIEW * pnmHTMLView = (NM_HTMLVIEW *)lParam;
szURL = pnmHTMLView->szTarget;
szPostData = pnmHTMLView->szData;
dwFlags = pnmHTMLView->dwFlags;
pszHeaders = pnmHTMLView->szExInfo;

Parameters

• szURL
  A null-terminated string that contains the navigation URL.

• szPostData
  A null-terminated string that contains the navigation POST data.

• dwFlags
  The following table gives various values and descriptions.

  Value	Description
  NAVIGATEFLAG_REFRESH	The navigation is a forced refresh of the URL content from the server, without checking expiration time or last-modified time.
  NAVIGATEFLAG_RELATIVE	The navigation is relative to the current page.
  NAVIGATEFLAG_ENTERED	The user entered the URL for the navigation.
  NAVIGATEFLAG_IGNORETARGET	The navigation is ignoring the TARGET attribute (if navigated via an <A HREF> tag.
  NAVIGATEFLAG_GETFROMCACHE	The navigation loads the content from the cache, without checking expiration time. Goes online only if there is no cache.
  NAVIGATEFLAG_NOCACHE	The content of the navigation will not be cached.
  NAVIGATEFLAG_RELOAD	Same as NAVIGATEFLAG_REFRESH, except that the referer on the HTTP request does not get set, and the content may be loaded from the cache if it has not expired.
  NAVIGATEFLAG_RESYNCHRONIZE	The navigation checks the server to see that the most recent content is available. This will allow the HTML control to go online without checking the expiration time. Then, the underlying code will compare the "last modified" time with the server, and download the more recent content, if necessary.

• pszHeaders
  A null-terminated string that contains the headers sent to the server for the navigation.

Return Value

The return value is ignored by the control.

Remarks

The information contained in the szURL parameter returned by NM_BEFORENAVIGATE is the navigation URL as it appeared in the SendMessage argument list before being composed into a complete and valid navigation URL. The information contained in the szURL parameter returned by NM_NAVIGATECOMPLETE is the complete navigation URL.

Example

To navigate to msn.com:

SendMessage(g_hWndCtrl, DTM_NAVIGATE, 0, (LPARAM)TEXT("https://msn.com/));

This actually navigates to https://www.msn.com. The szURL parameter returned by NM_BEFORENAVIGATE is "https://msn.com", but the szURL parameter returned by NM_NAVIGATECOMPLETE is "https://www.msn.com".

Requirements

See Also

Reference

HTML Control API Notifications
DTM_NAVIGATE
DTM_STOP
NM_DOCUMENTCOMPLETE
NM_NAVIGATECOMPLETE
NM_HTMLVIEWA
NM_HTMLVIEWW