c++ open62541 查询某一节点下所有变量节点，非变量节点不储存

您好！可以使用open62541提供的UA_Client_forEachChildNode方法遍历某一节点下的所有子节点，然后对每个子节点进行判断，如果是Variable节点则储存，否则不储存。以下是示例代码：

void browseChildren(UA_Client *client, UA_NodeId nodeId, std::vector<UA_NodeId>& variableNodes) {
    UA_BrowseRequest request;
    UA_BrowseRequest_init(&request);
    request.requestedMaxReferencesPerNode = 0;
    request.nodesToBrowse = UA_BrowseDescription_new();
    request.nodesToBrowseSize = 1;
    request.nodesToBrowse[0].nodeId = nodeId;
    request.nodesToBrowse[0].browseDirection = UA_BROWSEDIRECTION_FORWARD;
    request.nodesToBrowse[0].referenceTypeId = UA_NODEID_NUMERIC(0, UA_NS0ID_HASCHILDNODE);
    request.nodesToBrowse[0].includeSubtypes = true;
    request.nodesToBrowse[0].nodeClassMask = UA_NODECLASS_VARIABLE;

    UA_BrowseResponse response = UA_Client_Service_browse(client, request);
    if (response.responseHeader.serviceResult == UA_STATUSCODE_GOOD && response.resultsSize > 0) {
        for (size_t i = 0; i < response.results[0].referencesSize; ++i) {
            UA_ReferenceDescription *rd = &(response.results[0].references[i]);
            if (!UA_NodeId_equal(&rd->nodeId.nodeId, &UA_NODEID_NUMERIC(0, UA_NS0ID_HASCOMPONENT))) {
                variableNodes.push_back(rd->nodeId.nodeId);
            }
        }
    }

    UA_BrowseRequest_deleteMembers(&request);
    UA_BrowseResponse_deleteMembers(&response);
}

其中，client是UA_Client对象，nodeId是要查询的节点的NodeId对象，variableNodes是存储Variable节点NodeId的vector。