小编rud*_*tti的帖子

setx永久修改环境变量.
set仅在批处理脚本持续时间内使变量可用.
有没有办法设置变量以保持其值,直到系统重新启动？
例如,在我的批处理文件中,我正在检查变量是否设置如下:

if %MYVAR% == 1 (
<block>
)

考虑这个课程:

class Packet {
public:
  Packet();
  ~Packet();
  void allocateBuffer(unsigned int size);
  void deallocateBuffer();
  char* getBuffer() const;
private:
  char* buffer;
};

使用以下方法:

Packet::Packet():
  buffer(NULL) {
  std::cout << "[DEBUG] Construct Packet class..." << std::endl;
}

void Packet::allocateBuffer(unsigned int size) {
  if (!(buffer)) {
    buffer = new char[size];
#ifdef DEBUG
    std::cout << "Allocate buffer memory..." << std::endl;
#endif
  }
}

void Packet::deallocateBuffer() {
  if (buffer) {
   delete[] buffer;
   buffer = NULL;
#ifdef DEBUG
    std::cout << "Deallocate buffer memory..." << std::endl;
#endif
  }
} …