如何将整个流读入 std::string?

2022-01-07 00:00:00 string stream c++

我正在尝试将整个流(多行)读入一个字符串.

I'm trying to read an entire stream (multiple lines) into a string.

我正在使用这段代码，它可以工作，但它冒犯了我的风格……当然有更简单的方法吗?也许使用字符串流?

I'm using this code, and it works, but it's offending my sense of style... Surely there's an easier way? Maybe using stringstreams?

void Obj::loadFromStream(std::istream & stream)
{ 
  std::string s;

  std::streampos p = stream.tellg();  // remember where we are

  stream.seekg(0, std::ios_base::end); // go to the end
  std::streamoff sz = stream.tellg() - p;  // work out the size
  stream.seekg(p);        // restore the position

  s.resize(sz);          // resize the string
  stream.read(&s[0], sz);  // and finally, read in the data.

<小时>实际上，对字符串的 const 引用也可以，这可能会使事情变得更容易...

Actually, a const reference to a string would do as well, and that may make things easier...

const std::string &s(... a miracle occurs here...)

推荐答案

怎么样 

std::istreambuf_iterator<char> eos;
std::string s(std::istreambuf_iterator<char>(stream), eos);

(如果不是 MVP 可能是单线)

(could be a one-liner if not for MVP)

2011 年之后的编辑，这种方法现在拼写

post-2011 edit, this approach is now spelled

std::string s(std::istreambuf_iterator<char>(stream), {});

相关文章