c++ - 当顶点具有属性时，write_graphviz 不起作用

Question

我正在学习 boost::graph 并尝试将 name 属性添加到 Vertex。然而，这样做之后，write_graphviz 不会保存任何东西(没有这个属性，它可以工作)。

头文件:

struct VertexProps
{
    std::string name;
};

struct EdgeProps
{
    double weight;
};

using Graph = boost::adjacency_list<boost::setS, boost::vecS, boost::directedS, VertexProps, EdgeProps>;
using Vertex = boost::adjacency_list<>::vertex_descriptor;
using Edge = std::pair<boost::adjacency_list<>::edge_descriptor, bool>;
using EdgeList = std::pair<boost::adjacency_list<>::edge_iterator,
    boost::adjacency_list<>::edge_iterator>;

Cpp文件:

Vertex vertex = boost::add_vertex({std::move(vertexName)}, g);

std::filebuf fb;
fb.open("output.txt", std::ios::out);
std::ostream os(&fb);
write_graphviz(os, g, boost::make_label_writer(get(&VertexProps::name, g)), boost::make_label_writer(get(&EdgeProps::weight, g)));
fb.close();

文件应该包含图表，但我只能看到:

digraph G {
}

Answer 1

不清楚你有什么不同，但这是一个基于上述内容的独立示例:

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#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graphviz.hpp>

struct VertexProps { std::string name; };
struct EdgeProps { double weight; };

using Graph = boost::adjacency_list<boost::setS, boost::vecS, boost::directedS, VertexProps, EdgeProps>;

int main(){
    Graph g;

    auto vertex = add_vertex({"MyVertexName"}, g);

    write_graphviz(std::cout, g,
        make_label_writer(get(&VertexProps::name, g)),
        make_label_writer(get(&EdgeProps::weight, g)));
}

哪个打印

digraph G {
0[label=MyVertexName];
}