stockctrl.txt

一个补票分析程序

Stock Ticker is an application that downloads stock information from the web
and displays it in a control that scrolls the data from right to left.  The
data is updated at set intervals (dertermined by the user).

Stock Ticker contains 4 parts: Shared ATL component (stockquotes),
ATL control (stocktickeratl), ISAPI Extension DLL (stocksourcemfc)
and an MFC container app (containermfc).

To use the Stock Ticker application first register (using regsvr32) the
2 dlls (stockquotes.dll and stocktickeratl.dll).  Then just run
containermfc.exe (you can rename this if you want).  You also may need to
register ATL.DLL.

The ISAPI Extension DLL acts like a stock data source and should be put on a
machine that has IIS installed.

Click the right mouse button in the client area of the application to bring up
a popup menu that allows you to change the properties of Stock Ticker.

"Stocks"
	Brings up a dialog box that allows you to add or remove the stock symbols
	to monitor.  The dialog will be initialized with the current list of
	stock symbols.

"Update Now"
	Tells Stock Ticker to update the stock information from the web now.

"Properties"
	Brings up the properties dialog.  The properties dialog has 3 property
	pages: color, font and a custom page for Stock Ticker.
	The Stock Ticker page allows you to change the following properties:
		o Ticker speed:  Move the slider to increase or decrease the
		  rate at which the stock information scrolls from right to left.
		o Update Interval:  This is the time in minutes between updates.
		o ISAPI Extension DLL URL: Enter the full URL to the ISAPI Extension DLL.
		  Append the following the the end (no quotes): "?QueryForStocks?Symbol=".
		o MS Investor URL:  Enter the full URL (if different than the default)
		  of Microsoft Investor web site.  When this application was developed
		  the URL was: "http://moneycentral.msn.com/scripts/webquote.dll?Symbol="

When specifying the URL for either the ISAPI Extension DLL or MS Investor you
need to also include the component that is responsible for returning the HTML
that contains the stock information. For example, MS Investor's component
is "quote.asp".  The other part of the URL is the parameters to the component,
such as "?Symbol=".

The Stock Ticker Sample has a dependency on the MS Investor Web Page Format.
If the format of the page changes, then the Ticker will show <NA> after the
stock symbol. To make it work you would have to modify the 
CSQSMSInvestor::SetStockInfo() and CSQSMSInvestor::ParseStockInfo() methods to 
work with the new format of the pages. Look at the 
"How to add stock source web sites:" below for tips on how to do this.

The system menu has 2 addition menu items:
	o "About Stock Ticker" : Brings up the about dialog box.
	o "Stay On Top" : If checked Stock Ticker will stay on top of all other
	  applications, otherwise it behaves like other applications (can be
	  hidden by other apps).


The following section describes in a little more detail each of the components
that make up the Stock Ticker application.

Features Used:
---------------
ATL COM object.
ATL Dialog object.
ATL control.
MFC Internet (WinINet) classes.
MFC ISAPI Extension DLL.
Connection points.
Persistence.
Custom enumerators.
Standard C++ Library.

Stock Quotes Component:
-----------------------
Shared component (ATL object) created with the ATL wizard.  Uses MFC's WinINet
support and other utility classes.  Stockquotes is responsible for keeping
track of the stocks to be monitored and for updating the stock information from
the web.  There are 2 ways an application can use this component: Synchronous and
asynchronous updates.  If the StartUpdating() method is called then a child
thread will be created and the function will return immediately.  The child
thread creates a timer and waits until the update interval has elapsed.  It
then asks the Stock Quotes component to update.  Subsequent calls to Update()
will post a thread message to the child thread telling it that an update
should occur now.  Update() then returns immediately.  In Synchronous mode
Update() blocks until the download is complete.

Stock Quotes keeps track of stock data source objects that represent the
web sites the stock information is downloaded from.  When it comes time
to update the stock information Stock Quotes will go through the list of stock
data sources and attempt to download the information. If the attempt fails,
then the next stock data source is tried.  If all the stock data sources
failed to download the information "<NA>" will appear in the ticker window
after the stock symbol.

The default stock data sources are MS Investor and the ISAPI Extension DLL.
See below for instruction on how to add your own.

ISAPI Extension DLL:
--------------------
In the event that MS Investor can't be used you can use this DLL.  The ISAPI
Extension DLL does not return "real" stock data.  Instead when you request
data for a stock it checks whether the stock symbol is in its list of known
stocks.  If so then it retrieves the data and adjusts (randomly) the
current stock price up or down.  If the stock symbol is new it is added to
the list and an initial stock price is set.

Stock Ticker Control:
---------------------
This control was created with the ATL control wizard.  It uses MFC mostly to
make some things easier.

This control can be used outside of the Stock Ticker application.

Uses the Stock Quotes component to handle the stock information and updates.

When it comes time to save itself to a stream the control will also
ask the Stock Quotes component to save itself.

On startup the control will create the Stock Quotes component and ask it to
start updating stock information.  The control then starts a timer that it
uses for the draw/render loop.  When stock data has been updated the
Stock Quotes component will notify the control (through a connection point).
The control then gets all the stock information from the Stock Quotes component
and creates a string out of it.  This string is what is drawn in the control
and scrolls from right to left.

Stock Ticker Container:
------------------------
An MFC ActiveX Control container create with the MFC AppWizard.  Will save its
size and position when shutdown and restore its state when restarted.

Other than persistence control and menu handling the container really doesn't do
much else.

How to add stock source web sites:
-----------------------------------
You may want to add your own stock source web site at some point, here is a step
by step description of how to do it.

The stock data comes from the web site in HTML form and must be parsed to
find the current price and the price change since the last update.
The Stock Quotes component handles this parsing by looking for 2 keywords
(for example: "Current:", "Change:") and then reading the data that comes after
that looks like a number (fractional or decimal).

Because the web sites that you are using to get the stock data may change you
may have to change the algorithm that the Stock Quotes component uses to
get the stock information.

Steps:
1. Edit stockquotes\stockquotes_.h and find "CSQSMSInvestor" or "CSQSISAPIDll"
   classes.  You can use these as examples.
2. Create new classes derived from "CStockQuoteSource".
3. In the constructor set the "m_strURL" data member to the full URL to the
   web site to get the data from, including the command to retrieve the stock data.
4. Depending on the format of the HTML sent back from the web site override
   "SetStockInfo()" and/or "ParseStockInfo()".
5. Rebuild component and register.

If you get something like "ABC: <NA>", where "ABC" is the stock symbol, then
either the site could not be connected to or the stock quotes source class
you created could not find the stock information from the HTML.

Miscellaneous:
--------------
It is possible that the format (decimial or fractional) of the stock data may
be different among the various stocks you have chosen to monitor.  This can
happen as a result of data being retrieved from different web sites, Stock
Ticker makes no attempt to "normalize" the data to make it consistent.

Troubleshooting:
------------------
PROBLEM:  The stock color and font property pages don't show up in the
property dialog.
SOLUTION:  Register msstkprp.dll.