C ++从字符串中去除非ASCII字符(C++ Strip non-ASCII Characters from string)

 在你开始之前; 是的，我知道这是一个重复的问题，是的，我已经看过发布的解决方案。 我的问题是我无法让他们工作。 
 
bool invalidChar (char c)
{ 
    return !isprint((unsigned)c); 
}
void stripUnicode(string & str)
{
    str.erase(remove_if(str.begin(),str.end(), invalidChar), str.end()); 
}
 
 我在“Prusæus，Ægyptians”上测试了这个方法，它也没有做任何事情，我也试图用isalnum替代isprint 
 
 真正的问题发生在我的程序的另一部分中时，我将string-> wstring-> string转换。 如果string-> wstring转换中存在unicode字符，则转换会变得很慢。 
 
 参考： 
 
 如何从字符串中去除非ASCII字符？ （在C＃中） 
 
 如何去除c ++中的字符串中的所有非字母数字字符？ 
 
 编辑： 
 
 我仍然想删除所有非ASCII字符，无论它是否有帮助，这里是我崩溃的地方： 
 
// Convert to wstring
wchar_t* UnicodeTextBuffer = new wchar_t[ANSIWord.length()+1];
wmemset(UnicodeTextBuffer, 0, ANSIWord.length()+1);
mbstowcs(UnicodeTextBuffer, ANSIWord.c_str(), ANSIWord.length());
wWord = UnicodeTextBuffer; //CRASH
 
 错误对话框 
 
 MSVC ++调试库 
 
 调试断言失败！ 
 
 程序：// myproject 
 
 文件：f：\ dd \ vctools \ crt_bld \ self_x86 \ crt \ src \ isctype.c 
 
 行：//上方 
 
 表达：（无符号）（C + 1）<= 256 
 
 编辑： 
 
 进一步加剧了这个问题：我正在读取的.txt文件是ANSI编码的。 所有内容都应该是有效的。 
 
 解： 
 
bool invalidChar (char c) 
{  
    return !(c>=0 && c <128);   
} 
void stripUnicode(string & str) 
{ 
    str.erase(remove_if(str.begin(),str.end(), invalidChar), str.end());  
}
 
 如果有人想复制/粘贴，我可以检查这个问题。 
 
 编辑： 
 
 以供将来参考：尝试使用__isascii，iswascii命令 

Before you get started; yes I know this is a duplicate question and yes I have looked at the posted solutions. My problem is I could not get them to work. 
 
bool invalidChar (char c)
{ 
    return !isprint((unsigned)c); 
}
void stripUnicode(string & str)
{
    str.erase(remove_if(str.begin(),str.end(), invalidChar), str.end()); 
}
 
I tested this method on "Prusæus, Ægyptians," and it did nothing I also attempted to substitute isprint for isalnum
 
The real problem occurs when, in another section of my program I convert string->wstring->string. the conversion balks if there are unicode chars in the string->wstring conversion. 
 
Ref:
 
How can you strip non-ASCII characters from a string? (in C#)
 
How to strip all non alphanumeric characters from a string in c++?
 
Edit:
 
I still would like to remove all non-ASCII chars regardless yet if it helps, here is where I am crashing:
 
// Convert to wstring
wchar_t* UnicodeTextBuffer = new wchar_t[ANSIWord.length()+1];
wmemset(UnicodeTextBuffer, 0, ANSIWord.length()+1);
mbstowcs(UnicodeTextBuffer, ANSIWord.c_str(), ANSIWord.length());
wWord = UnicodeTextBuffer; //CRASH
 
Error Dialog
 
MSVC++ Debug Library
 
Debug Assertion Failed!
 
Program: //myproject
 
File: f:\dd\vctools\crt_bld\self_x86\crt\src\isctype.c
 
Line: //Above
 
Expression:(unsigned)(c+1)<=256
 
Edit:
 
Further compounding the matter: the .txt file I am reading in from is ANSI encoded. Everything within should be valid.
 
Solution:
 
bool invalidChar (char c) 
{  
    return !(c>=0 && c <128);   
} 
void stripUnicode(string & str) 
{ 
    str.erase(remove_if(str.begin(),str.end(), invalidChar), str.end());  
}
 
If someone else would like to copy/paste this, I can check this question off.
 
EDIT:
 
For future reference: try using the __isascii, iswascii commands

原文：https://stackoverflow.com/questions/10178700