[c++][语言语法]stringstream iostream ifstream

std::ifstream t;
int length;
t.open("file.txt");      // open input file
t.seekg(0, std::ios::end);    // go to the end
length = t.tellg();           // report location (this is the length)
t.seekg(0, std::ios::beg);    // go back to the beginning
buffer = new char[length];    // allocate memory for a buffer of appropriate dimension
t.read(buffer, length);       // read the whole file into the buffer
t.close();                    // close file handle

#include <string>#include <fstream>#include <streambuf>std::ifstream t("file.txt");std::string str((std::istreambuf_iterator<char>(t)),std::istreambuf_iterator<char>());

#include <string>#include <fstream>#include <sstream>std::ifstream t("file.txt");std::stringstream buffer;buffer << t.rdbuf();std::string contents(buffer.str());