How to resolve " invalid operands of types 'const char [ ]' and 'const char*' to binary 'operator+' "

Question

I use Qt Creator and this code :

string execpath = "";
execpath += (QCoreApplication::applicationDirPath()).toStdString();
WinExec("ffmpeg -f dshow -t 32 -i audio=\"virtual-audio-capturer\" -y "+(execpath.c_str())+"\\sound.mp3", SW_HIDE); // Loopback captured in sound.mp3

generate this issue on line 3 :

invalid operands of types 'const char [60]' and 'const char*' to binary 'operator+'

How to solve it?

Concatenate the strings first, and *then* call `.c_str()` on the concatenated `std::string` — Brian Bi, Feb 22 '14 at 17:12

score 3 · Accepted Answer · answered Feb 22 '14 at 17:16

3

You'll want something like:

execpath += (QCoreApplication::applicationDirPath()).toStdString();
std::string cmd = "ffmpeg -f dshow -t 32 -i audio=\"virtual-audio-capturer\" -y "
WinExec((cmd +execpath +"\\sound.mp3").c_str(), SW_HIDE);

answered Feb 22 '14 at 17:16

Mats Petersson

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execpath is a variable that I use a lot in my code but I guess you are right – AmirH Feb 22 '14 at 17:23
This works : WinExec(string("ffmpeg -f dshow -t 32 -i audio=\"virtual-audio-capturer\" -y "+execpath+"\\sound.mp3").c_str(), SW_HIDE); // Loopback captured in sound.mp3 – AmirH Feb 22 '14 at 17:24

How to resolve " invalid operands of types 'const char [ ]' and 'const char*' to binary 'operator+' "

1 Answers1