c++ - 使用消息在 ROS 上发送 C 数组

Question

我的 ROS 消息很简单:

int8[64] packet1

我在我的谈话节点中发布:

terp::Packet1 msg;
msg.packet1={0,1,0,1,0,1};
ROS_INFO("Packet in string form: %s", msg->packet1);
chatter_pub.publish(msg);
ros::spinOnce();

我在我的监听节点中检索:

void resolve_input1(const uint8_t msg[]) {
  if (sizeof(msg->packet1)/sizeof(msg->packet1[0])<MAX_MSG_LEN) {
    memcpy(msg1,msg->packet1);
    ROS_INFO("I heard: [%s]\n",msg1);
  } else
    ROS_ERROR("Message from node 1 too long");
}

但是，在制作项目时，我收到以下错误:

listener.cpp:16:19: error: request for member 'packet1' in '*msg',
which is of non-class type 'const uint8_t {aka const unsigned char}
  if (sizeof(msg->packet1)/sizeof(msg->packet1[0])<MAX_MSG_LEN) {

将 resolve_input1 的声明更改为:

void resolve_input1(const terp::Packet1 msg) {

编辑: 摆脱了那个错误，但是现在出现了一个新的错误，这是相似的；强调我对消息的困惑:

listener.cpp:16:17 error: base operand of '->' has non-pointer type
'const Packet1 {aka const terp::Packet1_<std::allocator<void> >}'
    if (sizeof(msg->packet1)/sizeof(msg->packet1[0])<MAX_MSG_LEN) {
                  ^

Answer 1

在 resolve_input1 中，msg 是 const uint8_t* 类型，因此您可能必须将其reinterpret_cast 为 const terp::Packet1* 在访问字段之前。

更新: 根据您的编辑，只需将 msg-> 更改为 msg.。