SAMPLE: WebBand.exe Hosts WebBrowser Control in an Explorer Band

WebBand is a Explorer band sample that demonstrates how to host the WebBrowser control in an Explorer Band. (For more information about Explorer bands, please see the REFERENCES section in this article.)

WebBand demonstrates how to deal with a lot of the complicated issues of hosting the WebBrowser control in an Explorer band, such as keystroke and navigation problems.

The following file is available for download from the Microsoft Download Center:
For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base: Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file. WebBand is a band object sample that demonstrates how to host the WebBrowser control in an Vertical/Explorer band. This sample is very similar to the Search band that comes with Internet Explorer 4.0 and later. To use WebBand, follow these steps.

1. Copy the WebBand.htm and Results.htm files to a location on your Web server that corresponds to the STARTUP_URL definition in the WBExplorerBar.cpp file. STARTUP_URL is defined as "http://localhost/webband.htm", which assumes that the files are located on the default directory of a Web server that is running on the same machine as the Web browser. You must change STARTUP_URL to reference a specific Web server if you want this sample to work on other computers within your network or if your Web server is not located on the same computer where you are running this sample.
2. Compile the sample code using Visual C++ 5.0 or 6.0 (see the notes below for information about compiling with Visual C++ 5.0).
3. After compiling and registering WebBand.dll, start Internet Explorer 4.0 or later, and choose WebBand Search from the View menu. If you are using Internet Explorer 4.0x, this will be located under the Explorer submenu of the View menu.

WebBand will load WebBand.htm, which contains a form with an edit box and Submit button and a couple of links to other Web pages. When you type in the edit box and click the Submit button, the Results.htm file will be loaded in the current window. If you click on one of the links on the WebBand.htm Web page, the URL will be loaded in the main Internet Explorer window. If you are running Internet Explorer 5.0 or higher then a button is added to Internet Explorer's toolbar that displays the WebBand when pressed. Adding buttons to the toolbar is not supported in Internet Explorer 4.

WebBand is able to get around the keystroke issues that are most commonly associated with hosting the WebBrowser control in an Explorer band. These keystroke issues often cause problems with the backspace and delete keys when focus is set to an edit box by clicking on it with the left mouse button. These problems are caused by focus problems. The problem is usually that Internet Explorer does not know that the band currently has the focus.

In order to alleviate these problems, WebBand implements IOleControlSite. In the IOleControlSite::OnFocus method, the WebBrowser's IInputObjectSite::OnFocusChangesIS must be called to tell the WebBrowser that WebBand now has the focus.

Whenever a key is pressed, three things occur:

1. WebBand's IInputObject::HasFocusIO method is called to see if WebBand currently has the focus.
2. The IInputObject::UIActivateIO method is called to tell WebBand that is being activated.
3. The IInputObject::TranslateAccelerator method is called. It is here that WebBand passes the keystroke to the hosted WebBrowser control. This causes accelerator keys such as backspace and delete to be processed.

Another feature of WebBand is that navigation will occur in the correct window. This is accomplished in a number of ways. When a page is loaded, WebBand sinks events for all anchors on the page through the "all" collection. When an anchor is clicked, the target of the navigation is changed from the band window to the main Internet Explorer window.

Using Internet Explorer 4.0, you are only able to navigate to WebBand.htm and Results.htm. The Back link on the search results page, has a fragment identifier (that is, bookmark) associated with it. This fragment identifier is currently named "#_mysearch." In the BeforeNavigate2 event handler, WebBand checks for this fragment identifier in the URL. If it exists in the URL, the target of the navigation is changed to the band window.

NOTE: This sample was created using Visual C++ 6.0. It will compile in Visual C++ 5.0 but you will see some compiler warnings due to new Visual C++ 6.0 compiler directives.

Explorer Bars/Band Objects in the MSDN Online Web Builder Workshop: BandObjs sample in the Internet Client SDK: Reusing the WebBrowser control: (c) Microsoft Corporation 1998, All Rights Reserved. Contributions by Scott Roberts, Microsoft Corporation.