c++文件读写总结

#ifndef _FILE_READ_WRITE_H_

#define _FILE_READ_WRITE_H_

#include <fstream>

//some global functions

//read some value according to type

template<typename T>

bool ReadFrom(T& value, std::istream& f)

{

if (f.good())

{

f.read((char*)&value, sizeof(T));

if (sizeof(T) == f.gcount())

return true;

}

return false;

}

template<typename T>

bool ReadFrom(T* value, int count, std::istream& f)

{

if (f.good())

{

f.read((char*)value, sizeof(T) * count);

if (count* sizeof(T) == f.gcount())

return true;

}

return false;

}

template<typename T>

T ReadFromConvert(int bytes, std::istream& f)

{

T val(0);

if (f.good())

{

vector<char> buff;

buff.assign(bytes, 0);

f.read(&buff[0], bytes);

if (bytes == f.gcount())

{

memcpy(&val, &buff[0], bytes);

}

}

return val;

}

template<typename T>

bool WriteTo(T& value, std::ostream& f)

{

if (f.good())

{

f.write((char*)&value, sizeof(T));

return f.good();

}

return false;

}

template<typename T>

bool WriteTo(const T* value, int count, std::ostream& f)

{

if (f.good())

{

f.write((char*)value, sizeof(T)*count);

return f.good();

}

return false;

}

/************************************************************************/

/* Gobal functions */

/************************************************************************/

#include <sstream>

template<typename T>

T Conver2T(const char* str)

{

T valuet;

istringstream istr(str);

istr >> valuet;

return valuet;

}

#endif //end of _FILE_READ_WRITE_H_