C ++无效转换为'char'到'const char *'[-fpermissive] |

Question

I have a problem with this code:

void keylist(char key)
{
   //check if the user presses a key
   if(GetAsyncKeyState(key))
   {
      string skey = key;
      buffer.append(skey);
      counter++;

   }
}

Everytime I try to run the program it gives me this error: CodeBlocks Projects\\CB32KLG\\main.cpp|66|error: invalid conversion from 'char' to 'const char*' [-fpermissive]|

Answer 1

It's because of this

string skey = key;

There's no overloaded constructor in string which only takes character as its input.See below the complete list:-

string();
string (const string& str); 
string (const string& str, size_t pos, size_t len = npos);  
string (const char* s); 
string (const char* s, size_t n);   
string (size_t n, char c);  
template <class InputIterator>
  string  (InputIterator first, InputIterator last);

To fix you can use:-

string skey(1, key);

Answer 2

  string skey = key;

There is no viable converting constructor in string that takes just a char .
Initialize it like this:

string skey{key};

Or this:

string skey(1, key);