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VC 21天 学习VC 的好东西

		<TD ALIGN="LEFT">Default level (all reasonable warnings)		</TD>
	</TR>
	<TR ALIGN="LEFT" VALIGN="TOP">
		<TD ALIGN="LEFT">Level 4		</TD>
		<TD ALIGN="LEFT">Very sensitive (good for perfectionists)		</TD>
	</TR>
</TABLE>

<H3><A NAME="Heading4"></A>Table E.2.&nbsp;Debug info settings.</H3>
<P>
<TABLE BORDER="1">
	<TR ALIGN="LEFT" VALIGN="TOP">
		<TD ALIGN="LEFT"><I>Setting</I></TD>
		<TD ALIGN="LEFT"><I>Debugging Information Generated</I></TD>
	</TR>
	<TR ALIGN="LEFT" VALIGN="TOP">
		<TD ALIGN="LEFT">None		</TD>
		<TD ALIGN="LEFT">Produces no debugging information--usually reserved for Release modes.		</TD>
	</TR>
	<TR ALIGN="LEFT" VALIGN="TOP">
		<TD ALIGN="LEFT">Line Numbers Only		</TD>
		<TD ALIGN="LEFT">This generates only line numbers that refer to the source code for functions and
			global variables. However, compile time and executable size are reduced.		</TD>
	</TR>
	<TR ALIGN="LEFT" VALIGN="TOP">
		<TD ALIGN="LEFT">C 7.0-Compatible		</TD>
		<TD ALIGN="LEFT">This generates debugging information that is compatible with Microsoft C 7.0. It
			places all the debugging information into the executable files and increases their
			size, but allows full symbolic debugging.		</TD>
	</TR>
	<TR ALIGN="LEFT" VALIGN="TOP">
		<TD ALIGN="LEFT">Program Database		</TD>
		<TD ALIGN="LEFT">This setting produces a file with a .pdb extension that holds the maximum level of
			debugging information, but doesn't create the Edit and Continue information.		</TD>
	</TR>
	<TR ALIGN="LEFT" VALIGN="TOP">
		<TD ALIGN="LEFT">Program Database for Edit and Continue		</TD>
		<TD ALIGN="LEFT">This is the default and usual debug setting. It produces a .pdb file with the highest
			level of debugging and creates the information required for the new Edit and Continue
			feature.		</TD>
	</TR>
</TABLE>

<H3><A NAME="Heading5"></A>Creating and Using Browse Information</H3>
<P>You can use the Source Browser tool to inspect your source code in detail. This
tool can be invaluable if you are examining someone else's code or coming back to
your own code after you haven't viewed it for awhile.</P>
<P>To use the Source Browser, you must compile the application with the Generate
Browse Info setting checked, in the C/C++ tab of the Project Settings dialog box.
To run the tool, press Alt+F12 or click the Tools menu and select the Source Browser
option. (The first time you run the tool, it will ask you to compile the browser
information.)</P>
<P>The first dialog box the Source Browser presents requests an Identifier to browse
for (as shown in Figure E.2). This identifier can be a class name, structure name,
function name, or global or local variable name in your application. After you have
entered an identifier, the OK button is enabled, and you can browse for details about
that identifier.</P>
<P><A HREF="javascript:popUp('30fig02.gif')"><B>FIGURE E.2.</B></A><B> </B><I>The
Browse dialog box requesting a symbol to browse.</I></P>

<P>Select Query offers various options for details pertaining to your chosen symbol.
You can choose from any of the following:</P>
<P>

<UL>
	<LI>Definitions and References. This option shows you all the files that have refer-ences
	to the specified identifier and whether they are references to the identifier (places
	where it is used in the code) or definitions (places where the identifier is defined),
	as shown in Figure E.3. The line numbers are listed along with the filenames in each
	file. By double-clicking one of the references or definitions, the code to which
	it refers will be loaded and shown in the Developer Studio editor at that specific
	position. This is very useful for tracking all the places that a specific variable
	or function is used.
</UL>

<P><A HREF="javascript:popUp('30fig03.gif')"><B>FIGURE E.3.</B></A><B> </B><I>Source
Browser showing definitions and references.</I></P>

<P><I></I>

<UL>
	<LI>File Outline. This option shows you all the classes, data, functions, macros,
	and types that are defined in the specified filename (identifier), as shown in Figure
	E.4. You can filter each type in or out by pressing relevant buttons along the top
	of the browser window.
</UL>

<P><A HREF="javascript:popUp('30fig04.gif')"><B>FIGURE E.4.</B></A><B> </B><I>The
file outline display of the source browser.</I></P>

<P><I></I>

<UL>
	<LI>Base Classes and Members. This arguably is one of the most useful options of
	the source browser. By specifying a class as the identifier, all the classes' hierarchy
	and member functions and variables at each hierarchy level are displayed (see Figure
	E.5). You can also set the filter options to show only certain types of member functions
	and variables.
</UL>

<P><A HREF="javascript:popUp('30fig05.gif')"><B>FIGURE E.5.</B></A><B> </B><I>The
Base Classes and Members view of the source browser.</I></P>

<P><I></I>

<UL>
	<LI>Derived Classes and Members. This view is also very useful and shows all the
	classes that are derived from the specified class, along with their own member functions
	and variables. You can also use the browser with the MFC classes to gain more insight
	into the MFC implementation, as shown with the MFC CWnd class in Figure E.6.
</UL>

<P><A HREF="javascript:popUp('30fig06.gif')"><B>FIGURE E.6.</B></A><B> </B><I>The
Derived Classes and Members view of the Source Browser showing CWnd-derived classes.</I></P>

<P><I></I>

<UL>
	<LI>Call Graph. The Call Graph option shows you all the functions that are called
	by a specified identifier and the files in which they are defined and implemented.
	This lets you quickly track the potential flow of a program.
	<P>
	<LI>Callers Graph. The corresponding Callers Graph option shows you all the functions
	that call the specified identifier. You can use this to track the possible callers
	of your specified function.
</UL>

<H3><A NAME="Heading6"></A>Using Remote and Just-in-Time Debugging</H3>
<P>The debugger includes tools that let you debug a program running on a remote machine
(even over the Internet via TCP/IP). This can be useful if you want to test your
application in a different environment other than your development machine. To do
this, you must have exactly the same versions of the .dll and .exe files on both
machines. After loading the project, you can debug it via a shared directory from
the remote machine by changing the Executable for Debug Session edit box to the path
and filename of your local .exe file (located in the Project Settings dialog box
under the Debug tab).</P>
<P>You must also add a path to the .exe file in the Remote Executable Path and File
Name edit box at the bottom of the Debug tab, leaving the Working Directory blank.
You can then start the remote debugger monitor on the remote computer by running
the MSVCMON.EXE program and connecting to it by clicking the Build menu and selecting
the Debugger Remote Connection option.</P>
<P>From the Remote Connection dialog box you can choose Local for a shared directory
debug session or Remote to debug via a TCP/IP connection. (You can set the address
by clicking Settings.) This will connect to the remote monitor that will start the
remote debugging session.</P>
<H3><A NAME="Heading7"></A>Installing the Remote Debugger Files</H3>
<P>You will also need the following files to run the remote debugger monitor on the
remote machine: MSVCMON.EXE, MSVCRT.DLL, TLN0T.DLL, DM.DLL, MSVCP5O.DLL, and MSDIS100.DLL.
These files can be found in your installed ...\Microsoft Visual Studio\Common\MSDev98\bin
subdirectory.</P>

<P>Just-in-time debugging lets you debug a program that was run normally (not through
the debugger) and then developed a problem. If you have Visual C++ installed on a
machine and this option is enabled, any program that develops a fault will be loaded
into a new Developer Studio session ready for debugging and show the code that caused
the crash.</P>

<P>This often raises a chuckle when Developer Studio itself crashes and then proceeds
to load another session of itself, offering you an assembly code view of where the
crash took place in the original for you to debug. It can be very useful to debug
your own applications when they crash unexpectedly (usually in a demonstration to
your boss). You can enable this option by clicking the Tools menu and selecting Options
to display the Options dialog box. Then select the Debug tab and ensure that the
Just-in-Time debugging check box is checked.</P>
<P>The OLE RPC debugging option on this tab is also very useful when developing COM
and DCOM applications because it lets the debugger traverse a function call into
another out-of-process program or .dll and lets another debugger take over for the
other process. It then hands control back when returning from the remote function
and works across networks and different computers.</P>
<P>
<H2><A NAME="Heading8"></A>Tracing and Single Stepping</H2>
<P>One of the most useful features of the Visual C++ debugging environment is the
interactive single stepping. This feature lets you step through the code one line
at a time and examine the contents of variables as you go. You can also set breakpoints
so that the program runs until it reaches a breakpoint and then stops at that point,
letting you step from that point until you want to continue running.</P>
<P>Trace statements and assertions are also very useful tools for finding program
faults. Trace statements let you display messages and variables from your program
in the output window as it runs through trace statements. You can use assertions
to cause the program to stop if a condition isn't TRUE when you assert that it should
be.</P>
<P>
<H3><A NAME="Heading9"></A>Using the TRACE Macro</H3>
<P>You can add TRACE macros to your program at various places to indicate that various
parts of the code have been run or to display the contents of variables at those
positions. The TRACE macros are compiled into your code in the debug configuration
and displayed in the Output window on the Debug tab, when you run your program through
the debugger.</P>
<P>You can safely leave in the TRACE macros when you perform a release build because
these macros are automatically excluded from the destination object.</P>
<P>You can display simple messages or output variable contents by passing a format
string as the first parameter to the TRACE macro. This format string is exactly the
same as you would pass to a printf() or CString::Format() function. You can specify
various special formatting codes such as %d to display a number in decimal, %x to
display a number in hexadecimal, or %s to display a string. The following parameters
should then correspond to the order of the formatting codes. For example, the code</P>
<P>
<PRE>int nMyNum = 60;
char* szMyString = &quot;This is my String&quot;;
TRACE(&quot;Number = %d, or %x in hex and my string is: %s\n&quot;,
          nMyNum, szMyString);
</PRE>
<P>will result in this output trace line:</P>
<P>
<PRE>Number = 60, or 3c in hex and my string is 
&Acirc;This is my String
</PRE>
<P>Listing E.1 shows the TRACE macro used to display the contents of an array before
and after sorting by a very inefficient but simple sort algorithm.</P>
<P>If you want to try the code shown in Listing E.1, you can use the AppWizard to
build a simple SDI framework. Simply add the code above the OnNewDocument() member
function of your document class and then call it by adding a DoSort() call into your
OnNewDocument() function.</P>
<P>You can run the application through the debugger (click Build, select Start Debug,
and choose Go from the pop-up menu) to see the output trace.</P>
<P>You must ensure that the output window is visible (click the View menu and select
Output) when the tabbed output window is shown (same as the compiler output). Ensure
that the Debug tab is selected.</P>
<P>
<H4>LISTING E.1.&nbsp;LSTE_1.CPP--A SIMPLE SORT ROUTINE TO DEMONSTRATE DEBUGGING
TECHNIQUES.</H4>
<PRE>1:  void Swap(CUIntArray* pdwNumbers,int i)
2:  {
3:      UINT uVal = pdwNumbers-&gt;GetAt(i);
4:      pdwNumbers-&gt;SetAt(i, pdwNumbers-&gt;GetAt(i+1));
5:      pdwNumbers-&gt;SetAt(i+1,uVal);
6:  }
7:
8:  void DoSort()
9:  {
10:      CUIntArray arNumbers;
11:      for(int i=0;i&lt;10;i++) arNumbers.Add(1+rand()%100);
12:
13:      TRACE(&quot;Before Sort\n&quot;);
14:      for(i=0;i&lt;arNumbers.GetSize();i++)
15:          TRACE(&quot;[%d] = %d\n&quot;,i+1,arNumbers[i]);
16: 
17:      BOOL bSorted;
18:      do
19:      {
20:          bSorted = TRUE;