跟踪与调试

/*
    许多C++程序员在跟踪代码时通常的做法是，定义一个简单的Trace类将诊断信息打印到日志文件中。程序员
可以在每个想要跟踪的函数中定义一个Trace对象，在函数的入口和出口Trace类可以分别写一条信息。
    缺点：增加程序开销，必须重新编译程序来打开或关闭跟踪。
    我的博客：http://blog.csdn.net/windows_nt
*/

class Trace{public:Trace(const CString &name);~Trace();void debug(const CString &msg);static BOOL traceIsActive;private:CString theFunctionName;};//合适的地方做初始化BOOL Trace::traceIsActive = TRUE;Trace::Trace(const CString &name) : theFunctionName(name){if (traceIsActive){OutputDebugString(L"Enter function: " + name + L"\n");}}void Trace::debug(const CString &msg){if (traceIsActive){OutputDebugString(msg);}}Trace::~Trace(){if (traceIsActive){OutputDebugString(L"Exit function: " + theFunctionName + L"\n");}}//以上的代码存在性能问题，优化版：class Trace{public:Trace(const TCHAR* name, ... );~Trace();void debug(const TCHAR* msg);static BOOL traceIsActive;private:CString* theFunctionName;};//合适的地方做初始化BOOL Trace::traceIsActive = TRUE;inline Trace::Trace(const TCHAR* name, ... ) : theFunctionName(NULL){va_list args;va_start(args, name);CString csMsg;csMsg.FormatV(name, args);va_end(args);  if (traceIsActive){CString strOutput; strOutput.Format(L"Enter function: %s\n", csMsg );OutputDebugString (strOutput);theFunctionName = new CString(csMsg);}}void Trace::debug(const TCHAR* msg){if (traceIsActive){OutputDebugString( *msg + L"\n");}}inline Trace::~Trace(){if (traceIsActive){OutputDebugString(L"Exit function " + *theFunctionName + L"\n");delete theFunctionName;}}//调用方式{#ifdef MyDebugTCHAR pOutputchar[] = L"OnBnClickedOk()";TCHAR pOutputchar2[] = L"OnBnClickedOk2()";Trace trace(_T("参数1：%s，参数2：%s"), pOutputchar, pOutputchar2);#endif}