C++读取文件到字符串的完整方法

#include <fstream>
#include <sstream>
#include <string>

std::string readFileToString(const std::string& filename) {
    std::ifstream file(filename, std::ios::binary);
    if (!file.is_open()) {
        throw std::runtime_error("无法打开文件");
    }
    
    std::stringstream buffer;
    buffer << file.rdbuf();
    return buffer.str();
}

#include <fstream>
#include <string>

std::string readFileToString(const std::string& filename) {
    std::ifstream file(filename, std::ios::binary);
    if (!file.is_open()) {
        throw std::runtime_error("无法打开文件");
    }
    
    return std::string((std::istreambuf_iterator<char>(file)),
                       std::istreambuf_iterator<char>());
}

#include <fstream>
#include <string>

std::string readFileToString(const std::string& filename) {
    std::ifstream file(filename, std::ios::binary);
    if (!file.is_open()) {
        throw std::runtime_error("无法打开文件");
    }

    file.seekg(0, std::ios::end);
    size_t size = file.tellg();
    file.seekg(0, std::ios::beg);

    std::string content(size, '\0');
    file.read(&content[0], size);
    return content;
}