调试小技巧

“Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.”
— Brian W. Kernighan

1. 中断进入调试器
1.1 c++
_asm { int 3 }

一个宏( macro )

#ifdef DEBUG
#define BREAKPOINT __asm int3
#else
#define BREAKPOINT
#endif

1.2 也可使用 _CrtDbgBreak() ，在crtdbg.h中定义

1.3 所有平台（x86、x64均可用）  __debugbreak() ，定义于intrin.h

1.4 csharp
System.Diagnostics.Debugger.Break();

1.5 其他
可用NULL指针、除零操作等。

2. 定义自己的 assert 宏

void __declspec(noreturn) __assertNoReturn(char *, int, char *);

#if defined(_PREFAST_)
// For PREfast runs
//
   #define myAssert(x) __assume(x)

#elif defined(DBG)
//
// For checked builds with a simple assert mechanism
// (where DBG is the checked build symbol)
//
// The following function call will not cause false-positive
// results because __assertNoReturn will not return. More complex
// macros might return. In that case, use __assume.
//
   #define myAssert(x) ((!(x))?__assertNoReturn(__FILE__, __LINE__, #x):1)
#else
// Free build
   #define myAssert(x)   // Nothing
#endif

3. 调试常用快捷键（VS）
F5 开始程序并进行调试
F10 step over, 逐行调试
F11 step into
shift + F11 step out
ctrl + shift + F10 ,set next statement
CTRL +* : SHOW NEWXT STATEMENT
条件断点：一个例子 name.Equals("Name3")
设置条件断点后，断点符号中间会有一个加号
在VS2010中，断点可以导入、输出
使用 Breakpoint Hit Count

4. 得到当前文件名称和当前行
(.net charp)c# 中的 __File__ __line__
string  currentFile= new  System.Diagnostics.StackTrace( true ).GetFrame(0).GetFileName();
int  currentLine =  new  System.Diagnostics.StackTrace( true ).GetFrame(0).GetFileLineNumber(); 

String MethodName = new System.Diagnostics.StackTrace().GetFrame(0).GetMethod().Name;

MethodBase.GetCurrentMethod().Name


MethodInfo.GetCurrentMethod().Name


[Conditional("DEBUG")]
void DebugFunc()
{
} 

调试时一些有用的快捷键（VS2010）

Shortcut Keys	Descriptions
Ctrl-Alt-V, A	Displays the Auto window
Ctrl-Alt-B	Displays the Breakpoints dialog
Ctrl-Alt-C	Displays the Call Stack
Ctrl-Shift-F9	Clears all of the breakpoints in the project
Ctrl-F9	Enables or disables the breakpoint on the current line of code
Ctrl-Alt-E	Displays the Exceptions dialog
Ctrl-Alt-I	Displays the Immediate window
Ctrl-Alt-V, L	Displays the Locals window
Ctrl-Alt-Q	Displays the Quick Watch dialog
Ctrl-Shift-F5	Terminates the current debugging session, rebuilds if necessary, and starts a new debugging session.
Ctrl-F10	Starts or resumes execution of your code and then halts execution when it reaches the selected statement.
Ctrl-Shift-F10	Sets the execution point to the line of code you choose
Alt-NUM *	Highlights the next statement
F5	If not currently debugging, this runs the startup project or projects and attaches the debugger.
Ctrl-F5	Runs the code without invoking the debugger
F11	Step Into
Shift-F11	Executes the remaining lines out from procedure
F10	Executes the next line of code but does not step into any function calls
Shift-F5	Available in break and run modes, this terminates the debugging session
Ctrl-Alt-H	Displays the Threads window to view all of the threads for the current process
F9	Sets or removes a breakpoint at the current line
Ctrl-Alt-W, 1	Displays the Watch 1 window to view the values of variables or watch expressions
Ctrl-Alt-P	Displays the Processes dialog, which allows you to attach or detach the debugger to one or more running processes
Ctrl-D,V	IntelliTrace Event

6. 使用OutputDebugString
vc中使用 OutputDebugString
c#可用:
debug中可见
System.Diagnostics.Debug.WriteLine("I am using dot net debugging");
release 和 debug中均可见
System.Diagnostics.Trace.WriteLine("I am using dot net tracing");

对话框
System.Windows.Forms.MessageBox.Show("Exception at File:Line:\n" + ExceptionToStr(e));

将输出重定向到文件：
System.Diagnostics.Trace.Listeners.Clear();
System.Diagnostics.Trace.AutoFlush=true;
System.Diagnostics.Trace.Listeners.Add(new System.Diagnostics.TextWriterTraceListener("app.log"));

//z 2013-04-28 10:23:21 [email protected][T7,L117,R5,V108]
7. vbscript 调试

Dim objIEDebugWindow

Debug "This is a great way to display intermediate results in a separate window."


Sub Debug( myText )
  ' Uncomment the next line to turn off debugging
  ' Exit Sub

  If Not IsObject( objIEDebugWindow ) Then
    Set objIEDebugWindow = CreateObject( "InternetExplorer.Application" )
    objIEDebugWindow.Navigate "about:blank"
    objIEDebugWindow.Visible = True
    objIEDebugWindow.ToolBar = False
    objIEDebugWindow.Width   = 200
    objIEDebugWindow.Height  = 300
    objIEDebugWindow.Left    = 10
    objIEDebugWindow.Top     = 10
    Do While objIEDebugWindow.Busy
      WScript.Sleep 100
    Loop
    objIEDebugWindow.Document.Title = "IE Debug Window"
    objIEDebugWindow.Document.Body.InnerHTML = _
                 "<b>" & Now & "</b></br>"
  End If

  objIEDebugWindow.Document.Body.InnerHTML = _
                   objIEDebugWindow.Document.Body.InnerHTML _
                   & myText & "<br>" & vbCrLf
End Sub

Notes:	(1)	objIEDebugWindow must be declared in the main script body, not in the subroutine (must be global)!
	(2)	Do not discard the objIEDebugWindow object at the end of the script, or your debug window will vanish!