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Items added in the manner shown above display the strLabel text as the message, followed by a link that says "Go There". If you click the link, the WMC navigates to the location specified in strDestination. You can provide a custom formatted message and link by specifying the NI_FLAG_MESSAGEBAR_CUSTOMMESSAGE  flag . See Custom link text.

The flags field of the NAVSETITEM structure dictates how the message bar item will be handled.

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Custom link text 

Anchor
CustomLinkText CustomLinkText

The default link text is Go There but it can be customised by providing your own message string with your link text surrounded by the <a></a> tags when inserting the element. To use a custom message you need to set the By default a message bar item contains user-supplied text followed by a hyperlink with the text Go There. You can supply a custom message that allows you to set the hyperlink text as well as place it anywhere within the message. To do so set the flag NI_FLAG_MESSAGEBAR_CUSTOMMESSAGE in flags field of the NAVSETITEM structure . and provide a message in strLabel, enclosing the hyperlink portion in <a></a> tags. e.g.

void AddMessageBarItem(LPCWSTR text, LPCWSTR link)
{
	// First get the root of the MESSAGEBAR domain
	NAVSETITEM messageBarRootData;
	memset(&messageBarRootData, 0, sizeof(NAVSETITEM));
	if( !NavGetItem(_T("MESSAGEBAR"), &messageBarRootData) )
	{
		return;														// Failed to find MESSAGEBAR root
	}
	NavHandle messageBarRoot = messageBarRootData.hItem;
 
	NAVSETITEM newItem;
	memset(&newItem, 0, sizeof(newItem));
	newItem.flags = NI_FLAG_MESSAGEBAR_CUSTOMMESSAGE;
	newItem.EventMask = NI_EVENT_MOUSE_LCLICK;

	newItem.strLabel = L"This is the text <a>with an embedded link</a> to navigate to";
	newItem.strDestination = _T("{Notifications}");	   // where to go to
	newItem.lParam = (LPARAM)this;
	newItem.pInterface = &gTaskInterfacenotificationInterface;
	NavInsertItem(hMessageBar, _T("NotificationWarning"), &newItem);
	NavHandle messageBarItem = newItem.hItem;
}

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