system()函数使用变量参数，string 转为char*

// 使用pandoc将md格式转为html
void mdtohtml(string file,string filename){
    // pandoc --standalone --self-contained API_First.md -f markdown -t html -o C:\Users\Administrator\Desktop\Q3_API_Release\API_CHM\API_First.html
    // pandoc --standalone API_First.md -f markdown -t html -o C:\Users\Administrator\Desktop\Q3_API_Release\API_CHM\API_First.html

    // system("\"F:\\Program Files\\7-Zip\\7z.exe\" a F:\\test.zip F:\\answer");

    // https://www.cnblogs.com/Pillar/p/4206452.html
    char s[256];
    const char *file_str = file.c_str();
    const char *filename_str = filename.c_str();

	sprintf_s(s,256,"%s%s %s%s%s","pandoc ./Split/", file_str, "-f markdown -t html -s -o ./API_CHM/", filename_str, ".html");
    cout << s << endl;
    system(s);
    return ;
}