类成员函数模板特化
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//header filenamespace odbclib{class MemoryBlock{public:typedef unsigned char byte;explicit MemoryBlock(size_t = 0xff) throw(runtime_error);MemoryBlock(MemoryBlock const&) throw(runtime_error);virtual ~MemoryBlock();MemoryBlock& initBlock(byte);void const* getRawBlock() const;void* getRawBlock();void writeRawBlock(void const*,size_t);size_t getSize()const;MemoryBlock& setSize(size_t) throw(runtime_error);template<typename T>T getValue() const{//TODO:may cross memory boundaryT *p = (T *)m_buffer;return *p;}template<typename T>MemoryBlock& setValue(T const& t){initBlock(0);memcpy(m_buffer,(void const*)&t,min(sizeof(T),m_size));return *this;}template<typename T,size_t N>MemoryBlock& setValue(T const (&t)[N]){T * p = (T *)m_buffer;T * end = (T *)((byte*)m_buffer + m_size);int i = 0;initBlock(0);while(end - p > 0)memcpy(p++,&t[i++],sizeof(T));return *this;}private:void * m_buffer;size_t m_size;};template<> string MemoryBlock::getValue()const;template<> MemoryBlock& MemoryBlock::setValue<string>(string const&);}?
//source filenamespace odbclib{MemoryBlock::MemoryBlock(size_t sz) throw(runtime_error):m_buffer(0),m_size(0){m_buffer = (byte*)::malloc(sz);if(!m_buffer)throw runtime_error("malloc failed!");m_size = sz;}MemoryBlock::MemoryBlock(MemoryBlock const& other) throw(runtime_error):m_buffer(0),m_size(0){m_buffer = (byte*)::malloc(other.m_size);if(!m_buffer)throw runtime_error("malloc failed!");m_size = other.m_size;memcpy(m_buffer,(void*)other.m_buffer,m_size);}MemoryBlock::~MemoryBlock(){::free(m_buffer);m_buffer = (void*)0;m_size = 0u;}void const* MemoryBlock::getRawBlock() const{return (void*)m_buffer;}void* MemoryBlock::getRawBlock(){return (void*)m_buffer;}void MemoryBlock::writeRawBlock(void const* mem,size_t memsz){memcpy(m_buffer,mem,min(memsz,m_size));}size_t MemoryBlock::getSize()const{return m_size;}MemoryBlock& MemoryBlock::setSize(size_t sz) throw(runtime_error){byte* newAddr =(byte*)::realloc(m_buffer,sz);if(!newAddr)throw runtime_error("realloc failed!");m_buffer = newAddr;m_size = sz;return *this;}MemoryBlock& MemoryBlock::initBlock(byte data){memset(m_buffer,data,m_size);return *this;}template<>string MemoryBlock::getValue()const{byte *lastByte = (byte*)m_buffer + m_size - 1;byte data = *lastByte;*lastByte = byte(0);string s((char const*)m_buffer);*lastByte = data;return s;}template<>MemoryBlock& MemoryBlock::setValue<string>(string const& s){initBlock(0);memcpy(m_buffer,s.data(),min(s.size(),m_size));*((byte*)m_buffer + m_size - 1) = byte(0);return *this;}}?通过 vc 2010 , g++ 4.5.2