window API一天一練之共享記憶體

今天學習win下共享記憶體的程序通訊，仿照qt的共享記憶體類，封裝了乙個簡單的類。雖然比不上qt的類那麼完善和強大，但是通過學習也達到了理解win共享記憶體的方式。

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class winsharedmemory  

;  [html]  

winsharedmemory::winsharedmemory( string szkey /*= ""*/ ):m_memkey(szkey)  

,m_islock(false),m_mutex(null),m_pmemory(null),m_size(0),m_filemapping(null)  

winsharedmemory::~winsharedmemory()  

bool winsharedmemory::createsize( int size )  

if (size < 1)  

m_size = size;  

m_filemapping = createfilemapping(invalid_handle_value,null,page_readwrite,0,m_size,m_memkey.c_str());  

if (m_filemapping == null)  

if (getlasterror() == error_already_exists)  

return true;  

}    

void * winsharedmemory::data()  

const void * winsharedmemory::constdata() const  

bool winsharedmemory::attach()  

}  return true;  

}    

bool winsharedmemory::lock()  

else  

}    

bool winsharedmemory::isattach()  

bool winsharedmemory::unlock()  

return true;  

}    

int winsharedmemory::size()  

void winsharedmemory::setkey( string szkey )  

string winsharedmemory::key()  

string winsharedmemory::geterrormessage()  

bool winsharedmemory::detach()  

m_size = 0;  

m_pmemory = null;  

cleanhandle();  

return true;  

}    

void winsharedmemory::cleanhandle()  

if (m_mutex)  

}   

qt的測速程式**：

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sharedmemory::sharedmemory(qwidget *parent, qt::wflags flags)  

: qdialog(parent, flags)  

sharedmemory::~sharedmemory()  

void sharedmemory::readdatafrommemoryslot()  

sharedmemory.createsize(size);  

sharedmemory.attach();  

sharedmemory.lock();  

char *pmemory = (char*)sharedmemory.data();  

char *ptext = new char[size];  

strcpy(ptext,pmemory);  

sharedmemory.unlock();  

sharedmemory.detach();  

m_ptextedit->settext(qstring::fromstdstring(ptext));  

}    

void sharedmemory::writedatatomemoryslot()  

sharedmemory.createsize(size);  

sharedmemory.attach();  

sharedmemory.lock();  

char *pmemory = (char*)sharedmemory.data();  

string text = m_ptextedit->toplaintext().tostdstring();  

strcpy(pmemory,text.c_str());  

sharedmemory.unlock();  

}    

void sharedmemory::resizeevent( qresizeevent *event )     

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