rapidjson - 将键更改为另一个值

这里是rapidjson的hello world。我怎样才能更改密钥"hello" to "goodbye"并从 json 中获取字符串？我的意思是我想解析 json，更改一些键并获取 json 字符串，就像{"goodbye" : "world"}.

const char json[] = "{ \"hello\" : \"world\" }";

rapidjson::Document d;
d.Parse<0>(json);

  const char *json = R"({"hello": "world"})";
  rapidjson::Document d;
  d.Parse<0> (json);

  rapidjson::Value::Member* hello = d.FindMember ("hello"); if (hello) {
    d.AddMember ("goodbye", hello->value, d.GetAllocator());
    d.RemoveMember ("hello");
  }

  typedef rapidjson::GenericStringBuffer<rapidjson::UTF8<>, rapidjson::MemoryPoolAllocator<>> StringBuffer;
  StringBuffer buf (&d.GetAllocator());
  rapidjson::Writer<StringBuffer> writer (buf, &d.GetAllocator());
  d.Accept (writer);
  json = buf.GetString();

附：你可能应该复制json之后因为它的内存将被释放d.

附言您还可以就地替换字段名称，而不删除它：

rapidjson::Value::Member* hello = d.FindMember ("hello");
if (hello) hello->name.SetString ("goodbye", d.GetAllocator());

或者在迭代期间：

for (auto it = d.MemberBegin(); it != d.MemberEnd(); ++it)
  if (strcmp (it->name.GetString(), "hello") == 0) it->name.SetString ("goodbye", d.GetAllocator());