c++ nlohmann::json 中文支持

c++ nlohmann::json 是当前排名第一人库，但是在解析中文时会有问题

std::string to_utf8(std::wstring& wide_string)
{static std::wstring_convert<std::codecvt_utf8<wchar_t>> utf8_conv;return utf8_conv.to_bytes(wide_string);
}void test_nlohmann() {using namespace nlohmann;nlohmann::json j;// 测试中文和英文提前解析std::string js1 = R"({"key": "中文"})";std::string js2 = R"(Not a json string)";std::wstring js3 = LR"({"name":"中文"})";std::wstring js4 = LR"("中文"})";bool jsonStringIsValid = json::accept(js1);bool notJsonStringIsValid = json::accept(js2);jsonStringIsValid = json::accept(js3);notJsonStringIsValid = json::accept(js4);nlohmann::json jt;jt["age"] = 1;jt["name"] = "张三";auto jt_out = jt.dump();auto dd = utf8_to_ascii(jt["name"].get<std::string>());// 要先转成宽字符std::wstring str_json = LR"({"age":"12","name":"中文"})";try {j = nlohmann::json::parse(str_json);auto str_out = j.dump();if (j.contains("name") && j["name"].is_string()) {std::string value = utf8_to_ascii(j["name"].get<std::string>());int c = 0;}}catch (nlohmann::json::parse_error& ex) {std::string what = ex.what();}// 生成带中文的测试json j2;std::wstring ws = L"中文";j2["id"] = 123;j2["encoded"] = CW2A(ws.c_str(), CP_UTF8);std::string out = j2.dump();int c = 0;
}

这样测试成功。