C ++将wchar_t反斜杠插入字符串 [英] C++ inserting wchar_t backslash into string

问题描述

我有一个宽字符：

  const wchar_t * charSet = L！\＃$％& '（）* +， - 。/ 0123456789：;？=？？\\\

 L@ABCDEFGHIJKLMNOPQRSTUVWXYZ [\\] ^ _ \\\

 L`abcdefghijklmnopqrstuvwxyz当我把它传递到文本处理器'\'（'\\\\\\\\\\\\\\\\\\\\\\\\\\反斜杠）不存在。现在如果我改为\\它
 
 
 
我得到编译时错误：
 
 
缺少关闭引用
 
 
那么如何将反斜杠放入这样的char字符串？
解决方案
至于您的原始代码
 code> L！\＃$％&'（）* +， - 。/ 0123456789：;< =>？\\\

  / pre> 
 
 
您再次错过转义引号字符 您会得到
  L！\\＃$％&' ）* +， - 。/ 0123456789：;？？\\\

  
现在未转义的在此时关闭文本。下一次出现的将打开一个新的文本，但它是不平衡的，因此编译器错误消息（你可以发现效果，甚至在这里的代码标记）。你需要添加再次转义 \ 以转义：
  L！\\\＃$％&'（）* +， - 。/ 0123456789：;< =>？\\\

 // ^^^修复此问题
  
 
 
 
 
 
 
与 \ 反斜杠和引号字符混合的转义字符很难阅读和维护更改。 p> 
 
 
由于最新的标准（ c ++ 11 ）你可以使用 原始字符字符串文字 ：
  #include< iostream& 
 #include< string> 
 
 int main（）{
 std :: wstring ws（LRdel（！\＃$％&'（）* +， - 。/ 0123456789：;& =>？）delL\\\

 LRdel（@ABCDEFGHIJKLMNOPQRSTUVWXYZ [\] ^ _）delL\\\

 LRdel（`abcdefghijklmnopqrstuvwxyz { }〜）delL\\\
）; 
 std :: wcout  return 0; 
} 
  
输出
 ！\ &'（）* +， - 。/ 0123456789：;" =？ 
 @ABCDEFGHIJKLMNOPQRSTUVWXYZ [\] ^ _ 
`abcdefghijklmnopqrstuvwxyz {|}〜
  
 
 
 
 
查看工作样本此处和支持当前标准的编译器的此处。
 
I have a wide char literal:
const wchar_t* charSet =  L" !\"#$%&'()*+,-./0123456789:;<=>?\n"
                                L"@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_\n"
                           L"`abcdefghijklmnopqrstuvwxyz{|}~\n";
When I pass it into text processor '\'(backslash) isn't there.Now if I put instead \\ it

I am getting compile time error: 

  
"missing closing quote"
So how do I put backslash into such a char string?
解决方案
As for your original code 
L" !\"#$%&'()*+,-./0123456789:;<=>?\n"
you simply missed escaping the quote character " again. Adding another \ you'll get 
L" !\\"#$%&'()*+,-./0123456789:;<=>?\n"
and the now unescaped " closes the literal at this point. The next occurrence of " will open a new literal but it's unbalanced, hence the compiler error message (you can spot the effect even in the code markup here). You need to add a further \ to escape the " again:
L" !\\\"#$%&'()*+,-./0123456789:;<=>?\n"
//  ^^^ Fix this




But managing escaped characters intermixed with \ backslash and " quote characters is pretty hard to read and to maintain with changes.

Since the latest standard (c++11) you can make use of raw character string literals:
#include <iostream>
#include <string>

int main() {
    std::wstring ws(LR"del( !\"#$%&'()*+,-./0123456789:;<=>?)del" L"\n"
                    LR"del(@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_)del" L"\n"
                    LR"del(`abcdefghijklmnopqrstuvwxyz{|}~)del" L"\n");
    std::wcout << ws;
    return 0;
}
Output
 !\"#$%&'()*+,-./0123456789:;<=>?
@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_
`abcdefghijklmnopqrstuvwxyz{|}~
No escaping necessary, you see.

See the working samples here and here for compilers supporting the current standards.

                        
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