从ifstream读取不会读取空格-Readingfromifstreamwon'treadwhitespace

I'm implementing a custom lexer in C++ and when attempting to read in whitespace, the ifstream won't read it out. I'm reading character by character using >>, and all the whitespace is gone. Is there any way to make the ifstream keep all the whitespace and read it out to me? I know that when reading whole strings, the read will stop at whitespace, but I was hoping that by reading character by character, I would avoid this behaviour.

我正在用C ++实现一个自定义词法分析器,当试图读取空格时,ifstream将不会读取它。我正在使用>>逐字逐句阅读,所有的空白都消失了。有没有什么方法可以让ifstream保留所有的空格并将它读出来给我?我知道在阅读整个字符串时,读取将停留在空白处,但我希望通过逐字逐句阅读,我会避免这种行为。

Attempted: .get(), recommended by many answers, but it has the same effect as std::noskipws, that is, I get all the spaces now, but not the new-line character that I need to lex some constructs.

尝试:.get(),由许多答案推荐,但它与std :: noskipws具有相同的效果,也就是说,我现在获得所有空格,但不是我需要使用某些结构的新行字符。

Here's the offending code (extended comments truncated)

这是违规代码(扩展注释被截断)

while(input >> current) {
    always_next_struct val = always_next_struct(next);
    if (current == L' ' || current == L'\n' || current == L'\t' || current == L'\r') {
        continue;
    }
    if (current == L'/') {
        input >> current;
        if (current == L'/') {
            // explicitly empty while loop
            while(input.get(current) && current != L'\n');
            continue;
        }

I'm breaking on the while line and looking at every value of current as it comes in, and \r or \n are definitely not among them- the input just skips to the next line in the input file.

我正在打破while行并查看当前的每个值,而\ r或\ n肯定不在其中 - 输入只是跳到输入文件中的下一行。

8 个解决方案

stream >> std::noskipws;

  while(input.get(current) && current != L'\n');
  continue;

//: get.cpp : compile, then run: get 

int main()
{
  char c;

  while (std::cin.get(c))
  {
    if (c == '/') 
    { 
      char last = c; 
      if (std::cin.get(c) && c == '/')
      {
        // std::cout <<"Read to EOL\n";
        while(std::cin.get(c) && c != '\n'); // this comment will be skipped
        // std::cout <<"go to next line\n";
        std::cin.putback(c);
        continue;
      }
     else { std::cin.putback(c); c = last; }
    }
    std::cout <

std::wifstream stream(filename, std::ios::binary);

std::wostringstream ss;
ss <

           /*Open the stream in default mode.*/
            std::ifstream myfile("myfile.txt");

            if(myfile.good()) {
                /*Read data using streambuffer iterators.*/
    vector buf((std::istreambuf_iterator(myfile)), (std::istreambuf_iterator()));

                /*str_buf holds all the data including whitespaces and newline .*/
                string str_buf(buf.begin(),buf.end());

                myfile.close();
            }